Answer:
Multiply the second equation by 9.
Step-by-step explanation:
To use the elimination method, you need to be able to add the equations and have one variable add to zero. That way you eliminate that variable.
The first equation has -9y. The second equation has y. If you multiply the second equation by 9, you will have 9y in the second equation. Then when you add equations, you will add -9y and 9y and will eliminate y.
Answer: Multiply the second equation by 9.
Answer:
Step-by-step explanation:
6x - 9y = 21
-6x -2y = -10
-11y = 11
y = -1
3x - 1 = 5
3x = 6
x = 2
(2, -1)
To measure a stone face carved on the side of a mountain, two sightings 700 feet from the base of the mountain are taken. If the angle of elevation to the bottom of the face is 35degreesand the angle of elevation to the top is 38 degrees,what is the height of the stone face
Answer:
Height of stone face is : 56.7 ft
Step-by-step explanation:
Kindly refer to the attached image for the diagram of the given conditions and values.
Let C be the base of mountain.
D be the point from where two sightings are taken.
AB be the stone face.
Angle of elevations:
[tex]\angle BDC =35^\circ\\\angle ADC =38^\circ[/tex]
To find:
Height of stone face = ?
AB = ?
Solution:
We can use trigonometric function of tangent here in two triangles [tex]\triangle BCD\ and\ \triangle ACD[/tex]:
[tex]In\ \triangle BCD :[/tex]
[tex]tan(\angle BDC) = \dfrac{Perpendicular}{Base} = \dfrac{BC}{CD}\\\Rightarrow BC = 700 \times tan35 ..... (1)[/tex]
[tex]In\ \triangle ACD :[/tex]
[tex]tan(\angle ADC) = \dfrac{Perpendicular}{Base} = \dfrac{AC}{CD}\\\Rightarrow AC = 700 \times tan38\\\Rightarrow AB +BC = 700 \times tan38\\\\\text{Using equation (1):}\\\Rightarrow AB + 700 \times tan 35 = 700 \times tan 38\\\Rightarrow AB = 700 \times tan 38-700 \times tan35\\\Rightarrow AB = 700 \times (tan 38-tan35)\\\Rightarrow AB = 700 \times 0.081\\\Rightarrow AB = \bold{56.7}\ ft[/tex]
So, Height of stone face is : 56.7 ft
A doctor prescribes a 100-mg antibiotic tablet to be taken every eight hours. Just before each tablet is taken, 20% of the drug remains in the body. (a) How much of the drug is in the body just after the sec- ond tablet is taken
Answer:
120 mg
Step-by-step explanation:
20% of 100 is 20 so that would be 20mg plus the 100mg they just took
100+20=120mg
i hope this helps you!
I need help with this please answer
Answer:
B. [tex]1\frac{1}{7}[/tex]
Step-by-step explanation:
[tex]-9\frac{2}{7}[/tex]=[tex]-\frac{65}{7}[/tex]
[tex]-10\frac{3}{7}[/tex]=[tex]-\frac{73}{7}[/tex]
[tex]-\frac{65}{7}[/tex]-([tex]-\frac{73}{7}[/tex])=8/7
8/7=[tex]1\frac{1}{7}[/tex]
Hope this helped!!!
9 is subtracted from 3 times the sum of 4 and 2
Answer:
9
Step-by-step explanation:
3 times the sum of 4 and 2 = 3*(4+2)
= 3 * 6
= 18
18 - 9 = 9
Identify the x-intercepts of the function graphed below.
Answer:
-2 and 3 along the horizontal line
Step-by-step explanation:
There are two axes, plural for axis; the two main lines. The one that runs vertically is the y axis and the one that runs horizontally is the x axis. Now when you see the parabola which is the curve, it meets at three points. The points are -2 , 6, and 3. the ones we are focusing on are the -2 and 3 since they are the numbers/points on the x axis
WILL GIVE BRAINLIEST FOR BEST ANSWER Maya wants to perform an experiment with a spinner labeled A, B, and C. The theoretical probabilities for each section are: P(A) = ½, P(B) = ¼, and P(C) = ¼. Which spinner could she use?
Answer: The answer is spinner B. There are 8 sections on the spinner and 4 of them have letter A, so P(A)= 1/2.
Answer:
spinner B
Step-by-step explanation:
there's 8 sides to the spinner and half of them have A on it.
HELPPPPPPPPPPPPPPPPPPPPPP
Answer:
x= 24, y= 33°
Step-by-step explanation:
MJ is part of the diameter of the circle and there is right angle between the diameter and HK
As the diameter and HK are perpendicular, HM=MK and mHJ= mJK
So,
x= 24and
y= 66°/2= 33°The number of bacteria in a culture is increasing according to the law of exponential growth. There are 105 bacteria in the culture after 2 hours and 325 bacteria after 4 hours. (a) Find the initial population. (Round your answer to the nearest whole number.) bacteria (b) Write an exponential growth model for the bacteria population. Let t represent the time in hours. y
a) The number of bacteria in the initial population is 34.
b) The exponential growth model is y = 34 * e^(kt)
Given data:
(a) To find the initial population, we can use the exponential growth formula:
y = A * e^(kt)
Where:
y = population at time t
A = initial population
k = growth rate
t = time
Given that there are 105 bacteria after 2 hours, so plug in these values into the formula:
105 = A * e^(k*2)
Similarly, given that there are 325 bacteria after 4 hours:
325 = A * e^(k*4)
We now have a system of equations:
105 = A * e^(2k)
325 = A * e^(4k)
To solve for A, divide the second equation by the first equation:
325/105 = e^(4k)/e^(2k)
Simplifying further:
325/105 = e^(2k)
Taking the natural logarithm of both sides:
ln(325/105) = ln(e^(2k))
ln(325/105) = 2k
Solving for k:
k = 0.56493
Substitute it back into one of the original equations to solve for A. Let's use the first equation:
105 = A * e^(2k)
Substituting k = ln(325/105) / 2:
105 = A * e^(2 * ln(325/105) / 2)
Simplifying:
105 = A * (325/105)
A = 105 * (105/325)
A ≈ 34 (rounded to the nearest whole number)
Hence, the initial population is approximately 34 bacteria.
(b) Now that we have the initial population, A, and the growth rate, k, we can write the exponential growth model for the bacteria population:
y = 34 * e^(kt)
where t represents the time in hours.
Hence, the exponential equations are solved.
To learn more about exponential growth factor, refer:
https://brainly.com/question/13674608
#SPJ4
Select the correct answer.
What is the value of this expression when g= -3.5?
8-[2g-5]
OA.
20
OB.
10
OC. 6
OD.
-4
Answer:
A. 20
Step-by-step explanation:
We are given the expression:
8-(2g-5)
and asked to find the value of the expression when g=-3.5. Therefore, we must plug -3.5 in for g.
8- (2(-3.5)-5)
Solve according to PEMDAS: Parentheses, Exponents, Multiplication, Division, Addition, Subtraction.
First, solve inside the parentheses. Begin by multiplying 2 and -3.5
8-(-7-5)
Next, subtract 5 from -7
8-(-12)
Finally, subtract -12 from 8.
8+12
20
The value of the expression 8-(2g-5) when g=-3.5 is 20. Therefore A. 20 is correct.
Determine whether the data set is a population or a sample. Explain your reasoning. The salary of each teacher in a school. Choose the correct answer below. A. Sample, because it is a collection of salaries for all teachers in the school comma but there are other schools. B. Population, because it is a subset of all schools in the city. C. Sample, because it is a collection of salaries for some teachers in the school. nothing D. Population, because it is a collection of salaries for all teachers in the school.
Answer:
D. Population, because it is a collection of salaries for all teachers in the school.
Step-by-step explanation:
In research, population refers to a complete set of subjects that share a characteristic and that the researcher is interested in. On the other hand, a sample is a subset of a population and it's usually the one the researcher takes to make a study with.
In this example, we have "The salary of each teacher in a school" since we are taking ALL the teachers of this school, this would be a population. If we were working with the salary of only a portion of the teachers of said school, it would be a sample.
Thus, the right answer is D. Population, because it is a collection of salaries for all teachers in the school.
The slope of a line is -4, and the y-intercept is -3. What is the equation of the line written in slope-intercept form?
Oy= 4x - 3
y=-4x + 3
Oy=-4x - 3
Answer:
y=-4x-3
Step-by-step explanation:
y=mx+b
y=b=-3 ( y intercept is when x=0, then y=b=-3)
y=-4x-3
(#1) Two thirds of Sandi's rose bushes bloomed this summer. One half of the roses that bloomed were pink. What part of Sandi's total rose bushes had pink blooms? If Sandi had 12 rose bushes, how many bore pink blooms? (#2) Mom has three quarters of a pound of chocolates. She divides the chocolates into portions that each weigh one eighth of a pound. If Mom eats one portion a day, for how many days will the chocolate last?
Answer:
The number of pink roses bloomed are 4.
Step-by-step explanation:
Given a graph for the transformation of f(x) in the format g(x) = f(kx), determine the k value.
ту
g(x)
f(x)
k= -4
k= -1/4
k= 1/4
k= 4
ASAP!!!!
Answer: C
1/4
Step-by-step explanation:
Given a graph for the transformation of f(x) in the format g(x) = f(kx),
This means that for every value of x, f(x) will take the value it would have had at kx, that is, the graph of f(x) is stretched by a factor of 1/k in the direction of positive x-direction.
Therefore, the value of k will be 1/4.
Answer:
k=4
Step-by-step explanation:
can someone help me fill out this chart
Answer:
is there a y part of this equation?
Step-by-step explanation:
In a newspaper, it was reported that yearly robberies in Springfield were down 10% to 90 in 2014 from 2013. How many robberies were there in Springfield in 2013?
Answer:
100.
Step-by-step explanation:
Let the number of robberies be x ( in 2013).
Then x - 0.10x = 90
0.90x = 90
x = 90 / 0.90
= 100.
Please answer it in two minutes
Answer:
36.33
Step-by-step explanation:
The given figure is pentagon
The sum of angles of polygon is (2n-4)*90 where n is number of sides of polygon
for pentagon number of sides is 5
thus, n = 5
\
sum of angles of pentagon = (2*5-4)*90 = 6*90 = 540
Given angles of pentagon
t, 149 , t+144, 3t -11 , t+40
Thus, sum of all these angles should be equal to 540
t + 149 + t+144 + 3t -11 + t+40 = 540
=> 6t + 322 = 540
=> 6t = 540 - 322 = 218
=> t = 218/6 = 36.33
Thus, t = 36.33
URGENT!!! PLEASE help me with this question!
Answer:
[tex]\huge\boxed{x = 8,\ but\ x = 3\ is\ extraneous}[/tex]
Step-by-step explanation:
[tex]\sqrt{x+1}+5=x\\\\\text{Domain:}\ x+1\geq0\to x\geq-1\\\\\sqrt{x+1}+5=x\qquad\text{subtract 5 from both sides}\\\sqrt{x+1}=x-5\qquad\text{square both sides}\\(\sqrt{x+1})^2=(x-5)^2\qquad\text{use}\ (\sqrt{x})^2=x\ \text{and}\ (a-b)^2=a^2-2ab+b^2\\x+1=x^2-2(x)(5)+5^2\\x+1=x^2-10x+25\qquad\text{subtract}\ x\ \text{and}\ 1\ \text{from both sides}\\0=x^2-11x+24[/tex]
[tex]ab=24;\ a+b=-11\\a=-8;\ b=-3\\\\x^2-11x+24=0\\x^2-8x-3x+24=0\qquad\text{distribute}\\x(x-8)-3(x-8)=0\qquad\text{distribute}\\(x-8)(x-3)=0\\\\\text{The product is 0 if one of the factors is 0. Therefore}\\(x-8)(x-3)=0\iff x-8=0\ \vee\ x-3=0\\x-8=0\qquad\text{add 8 to both sides}\\\boxed{x=8}\in D\\x-3=0\qquad\text{add 3 to both sides}\\\boxed{x=3}\in D[/tex]
[tex]\text{For}\ x=8:\\\sqrt{8+1}+5=8\\\sqrt{9}+5=8\\3+5=8\\8=8\qquad\bold{CORRECT}\\\text{For}\ x=3:\\\sqrt{3+1}+5=3\\\sqrt4+5=3\\2+5=3\\7=3\qquad\bold{FALSE}[/tex]
Segment MP is a diameter of circle O.
Which equation can be used to find mMN?
N
O MMN + 150 = 180
M
O MMN + 150 = 360
150°
O MMN - 150 = 180
OmMN – 150 = 360
a
Answer:
mMN + 150 = 180
Step-by-step explanation:
Circle O is shown. Line segment M P is a diameter. Line segment N O is a radius. Angle N O P is 150 degrees.
Given that:
NO is the radius and ∠NOP = 150°.
The angle addition postulate which states that a larger angle is formed when two smaller angles are placed side by side. If two angle x and y are small angles placed side by side, a big angle Z formed is given as:
z = x + y.
Therefore in circle O, using angle addition postulate:
mMN + ∠NOP = mMP
But mMP = 180° (angle on a straight line)
mMN + ∠NOP = 180°
mMN + 150 = 180
Three students used factoring to solve a quadratic equation? The equation was solve correctly by ______.The solutions of the equation are__________.
Answer:Keith
x=5,x=12
Step-by-step explanation:
Answer:
the answers are keith and -5,-12
Step-by-step explanation:
I just took the test and got a 5/5 the other person is incorrect.
HELP
Kevin has $25 in his checking
account. If Kevin has $2.20
less than 4 times the amount
that Molly has in her
account, what is the
amount of money in
Molly's account?
Answer:
$6.8
Step-by-step explanation:
Let x be the amount of money in Molly's amount
according to question,
4x-25=2.20
4x=2.20+25
4x=27.20
x=27.20/4
x=6.8
So,the amount of money in Molly's amont is $6.8
Answer: $6.80
Step-by-step explanation:
We will represent the amount of money that Molly has with a m. So it tells us the relationship between Kevin's amount and Molly's amount. It is says Kevin has 2.20 less that 4 times Molly's amount so we could represent it by the equation.
25 = 4m -2.20 solve for m.
+2.20 +2.20
27.20 = 4m
m= 6.8
4(6.8) = 27.20 - 25 = 2.20
Over summer, a dam’s water volume reduces from 20 megalitres to 4 megalitres. What fraction of the water in the dam has been lost?
Hey there! I’m happy to help!
Let’s first subtract 4 from 20 to see how much was lost.
20-4=16
Now, we see that 16 is a certain percent of twenty that we want to find. When talking about percents, the word “is” represents an equal sign. So, we can write this equation. We will have p represent our prevent.
16=20p (16 is a certain percent of 20)
Now, we solve by dividing both sides of the equation by 20 to isolate the p.
p=0.8
0.8 is 80% or 4/5, so 4/5 of the dam water has been lost.
Have a wonderful day! :D
Eggs come in packets of 12 and English muffins come in packets of 10. What is the least number of packages of each that can be bought to be able to make egg sandwiches with no muffins left over?
Answer:
The LCM of 12 and 10 is 60 so you would need to buy 60 / 12 = 5 packs of eggs and 60 / 10 = 6 packs of muffins.
Determine the equation of the line that is parallel to y=23x+4 and passes through the point (3,7).
Answer: y = 23x - 62
Step-by-step explanation:
Parallel lines have the same slope.
y = 23x + 4
m=23 b=4
Input x = 3, y = 7, & m = 23 into the Point-Slope formula to find the equation or the Slope-Intercept formula to find b (you already have m). I will choose the latter.
y = mx + b
7 = 23(3) + b
7 = 69 + b
-62 = b
m = 23, b = -62 --> y = 23x - 62
The base of a regular pyramid is a hexagon.
Answer:
The base of the regular pyramid is a square.
Step-by-step explanation:
help on radical functions
Answer:
A
Step-by-step explanation:
which of the following shows 210 angles in standard position
The 210 angles in the standard position are shown in figure (A) option (A) is correct.
What is an angle?When two lines or rays converge at the same point, the measurement between them is called an "Angle."
It is given that:
The measure of the angle:
= 210 degrees
The reference angle can be defined as the angle formed between the terminal side and the x-axis, known as the reference angle.
The angle between the x-axis and the y-axis is 90 degrees.
The angle between the y-axis and the negative x-axis is 90 degrees.
The angle between the negative x-axis and the arrow shown in the coordinate plane is 30 degrees.
Thus, the 210 angles in the standard position shown in figure (A) option (A) is correct.
Learn more about the angle here:
brainly.com/question/7116550
#SPJ2
Simplify: 42x^7-(-11x^7)
Answer: 53x^7
Step-by-step explanation:
Subtracting a negative is like adding.
Help me please with kim!
Answer: Kim - Resp after 24 months = $4,416.00
Kim - Technology Fund after 24 months = $1,120.06
Kim's Technology Fund has enough money to buy a laptop.
Kim's Savings (Resp) will last less than 6 months
Step-by-step explanation for Kim:
January - June 2019
$14.50 + 30($0.25) = $22.00/hr
$22/hr x 15 hr x 4 wks x 6 months = $7920 Gross Income
Resp (15%): $7920(0.15) = $1188CPP(5%): $7920(0.05) = $396EI(2%): $7920(0.02) = $158.40Taxable Income is $7920 - $1188 = $6732 (Annual Income $13,464)
Income Tax (0% for 0-9,000 Annual): $4500(0) = $0Income Tax (8% for 9-25,000 Annual): ($6732-$4500)(0.08) = $178.56→ $7,920 -($1188 + $396 + $158.40 + $0 + $158.40) = $5,999.04 Net Income
Tech Fund (5%): $5999.04(0.05) = $299.95
Food Expense (30%): $5999.04(0.3) = $1,799.71
Clothing Expense (30%): $5999.04(0.3) = $1,799.71
Entertainment Expense (25%): $5999.04(0.25) = $1,499.76
Miscellaneous Expense (10%): $5999.04(0.1) = $599.90
Other Expenses: $5,699.08
July - December 2019 (excluding August)
$22/hr x 20 hr x 4 wks x 5 months + $200 = $6800 Gross Income
Resp (15%): $6800(0.15) = $1020CPP(5%): $6800(0.05) = $340EI(2%): $6800(0.02) = $136Taxable Income is $6800 - $1020 = $5780 (Annual Income $12,512)
Income Tax (0% for 0-9,000 Annual): $4500(0) = $0Income Tax (8% for 9-25,000 Annual): ($5780-$4500)(0.08) = $102.40→ $6,800 - ($1020 + $340 + $136 + $0 + $102.40) = $5,201.60 Net Income
Tech Fund (5%): $5201.60(0.05) = $260.08
Food Expense (30%): $5201.60(0.3) = $1,560.48
Clothing Expense (30%): $5201.60(0.3) = $1,560.48
Entertainment Expense (25%): $5201.60(0.25) = $1,300.40
Miscellaneous Expense (10%): $5201.60(0.1) = $520.16
Other Expenses: $4,941.52
January - June 2020
same as January - June 2019
July - December 2020 (excluding August)
same as July - December 2019
[tex]\boxed{\begin{array}{l|r|r|r|r||r}\underline{KIM}&\underline{Jan-Jun'19}&\underline{Jul-Dec'19}&\underline{Jan-Jun'20}&\underline{Jul-Dec'20}&\underline{Totals\quad }\\Gross&\$7920.00&\$6800.00&\$7920.00&\$6800.00&\$29440.00\\Resp&\$1188.00&\$1020.00&\$1188.00&\$1020.00&\$4416.00\\Net&\$5999.04&\$5201.60&\$5999.04&\$5201.60&\$22401.28\\Other&\$5699.08&\$4941.52&\$5699.08&\$4941.52&\$21281.20\\Tech&\$299.95&\$260.08&\$299.95&\$260.08&\$1120.06\end{array}}[/tex]
Represent the following sentence as an algebraic expression, where "a number" is the letter x. You do not need to simplify.
One fifth of the square of a number
Answer:
The statement, one fifth of the square of a number is written as
[tex] \frac{1}{5} {x}^{2} [/tex]
Hope this helps you
Please solve this question for me
x = 65° and y = 77.5°.
Step-by-step explanation:The triangle with the 50 degree angle and x, is an isosceles triangle. That means that the other unlabeled angle is also equal to x degrees.
x + x + 50 = 180
2x + 50 = 180
2x = 130
x = 65°.
Since x = 65 degrees, and the two angles make a 90 degree angle, the other unlabeled angle will be 90 - 65 = 25 degrees.
Since the other triangle is also isosceles, that triangle has two angles that measure y degrees and one angle measuring 25 degrees.
y + y + 25 = 180
2y + 25 = 180
2y = 155
y = 77.5°.
Hope this helps!