Solve the system of equations x - y = 12 and x + 7y = -20 by combining the
equations.
Answer:
x=16, y=-4
Step-by-step explanation:
-1(x-y=12)
x+7y=-20
-x+y=-12
x+7y=-20
8y=-32
y=-4
x-4=12
x=16
Answer:
x= 8, y= -4
Step-by-step explanation:
You can subtract one equation by another to eliminate x
(x-y)-(x+7y)=12-(-20)
-8y = 32
y= -4
Substitute y = -4 in the first equation:
x-(-4) = 12
x =8
A survey of 71 families showed that:
40 have a son(s)
45 have a daughter(s)
18 had neither a son nor a daughter.
How many families had ONLY son(s)?
Answer:
108
Step-by-step explanation:
What is the value of x?
Answer:
122
Step-by-step explanation:
122 + 58 = 180
Answer:
x=122°
Step-by-step explanation:
58° and x form a straight angle, which is 180°.
x+58°=180°
x=180°-58°=122°
please help i don't get this
Answer:
-4
Step-by-step explanation:
what is 1/2 x 1/2 x 1/2 x 1/2
Answer:
0.0625
Step-by-step explanation:
Hope this helps :)
Have a nice day <3
Answer:
1/16
Step-by-step explanation:
Just multiply all numerators and all denominators: 1x1x1x1/2x2x2x2. That gives you your total of 1/16.
Mr. Brown has 1/4pan of lasagna left in the refrigerator. He wants to cut the lasagna into equal slices so he can have it for dinner for 3 nights. What fraction of the whole lasagna will he eat each night?
Answer:
1/12
Step-by-step explanation:
He has a 1/4 pan left and wants to divide that into 3 equal pieces. So in night he will eat 1/3 of what he has left from the 1/4 pan. To figure out how much one slice is from an entire pan:
1/4 * 1/3 = 1/12
Select all the expressions that show a way to decompose 512. A. 3 1/2+2 1/2 B. 3/6+2/6 C. 1 1/2+2 1/2+2 1/2 D. 1 1/2+1 1/2+3 1/2 E.1 1/2+1 1/2+2 1/2+2 1/2
Answer:
C,D,E
Step-by-step explanation:
Can you guys help me with this, please?
Answer:
G) y ≥ 1
Step-by-step explanation:
Range is all the y-values seen on the graph.
Since it starts at (0, 1), the lines just keep increasing so:
y ≥ 1
hellp me for a brainly
Answer:
25π or 78.5mm²
Step-by-step explanation:
[tex]A=3.14*5^{2} \\ =3.14*25\\ =78.5[/tex]
Answer:
78.5 mm² or answer D.Step-by-step explanation:
The formula for the area of a circle is
A = π*r²
Now we can rewrite with the radius. *Note* I am using 3.14 for pi to make it easier*
A = π*5²
Solve
5² = 25
25 * 3.14 = 78.5
Now since the measurements were done in millimeters, we will add mm to the end.
Also since it is area, we need to add ²
78.5 mm²
What is the missing side?
Answer:
x=5
Step-by-step explanation:
Area of triangle=1/2 * b * h
In this case b=10, h=x, and A=25
By substituting values in we can say:
[tex]A=\frac{1}{2} * b *h\\25=\frac{1}{2} * 10 * x\\25=5x\\x=5[/tex]
A swimming pool is to be drained. The pool is shaped like a rectangular prism with length 30 ft, width 18 ft, and depth 4 ft. Suppose water is pumped out of the
pool at a rate of 216 ft per hour. If the pool starts completely full, how many hours does it take to empty the pool?
hours ( NO LINKS , LINK WILL GET YOU BANNED )
Answer:
10 hours (I am not positive)
Step-by-step explanation:
We first want to find the volume of pool which is 30 x 18 x 4 = 2160.
Then you are going to divide by 216 to find how many hours it takes to drain the whole pool. (I'm not that big of an expert)
What is the distance between the points (5,7) and (3, 4) on the coordinate
plane?
A. 12.04 units
B. 7.28 units
C. 3.61 units
D. 8.54 units
Answer:
C) 3.61 units
Step-by-step explanation:
5 - 3 = 2
7 - 4 = 3
distance² = 2² + 3³ = 4 + 9 = 13
distance = √13 = 3.61
Solve the equation:
[3 2
5 5]
[x1
x2]+
[1
2]=
[2
-3]
9514 1404 393
Answer:
(x1, x2) = (3, -4)
Step-by-step explanation:
As with any 2-step linear equation, subtract the constant, then multiply by the inverse of the coefficient of the variable.
[tex]\left[\begin{array}{cc}3&2\\5&5\end{array}\right]\left[\begin{array}{c}x\\y\end{array}\right]+\left[\begin{array}{c}1\\2\end{array}\right]=\left[\begin{array}{c}2\\-3\end{array}\right]\\\\\left[\begin{array}{cc}3&2\\5&5\end{array}\right]\left[\begin{array}{c}x\\y\end{array}\right]=\left[\begin{array}{c}1\\-5\end{array}\right]\\\\\left[\begin{array}{c}x\\y\end{array}\right]=\dfrac{1}{5}\left[\begin{array}{cc}5&-2\\-5&3\end{array}\right]\left[\begin{array}{c}1\\-5\end{array}\right][/tex]
Performing the multiplication of the matrix by the vector gives the solution.
x = ((5)(1) +(-2)(-5))/5 = 15/5 = 3
y = ((-5)(1) +(3)(-5))/5 = -20/5 = -4
Using your variables, x1, x2, the solution is ...
(x1, x2) = (3, -4)
An initial population of 535 quail increases at an annual rate of 25%. Write an exponential function to model the quail population. What will the approximate population be after 5 years?
Answer: c
Step-by-step explanation:
Suppose that in a random selection of 100 colored candies, 21% of them are blue. The candy company claims that the percentage of blue candies is equal to 29%. Use the 0.01 significance level to test that claim.
Answer:
The pvalue of the test is 0.0784 > 0.01, which means that at this significance level, we do not reject the null hypothesis that the percentage of blue candies is equal to 29%.
Step-by-step explanation:
The candy company claims that the percentage of blue candies is equal to 29%.
This means that the null hypothesis is:
[tex]H_{0}: p = 0.29[/tex]
We want to test the hypothesis that this is true, so the alternate hypothesis is:
[tex]H_{a}: p \neq 0.29[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
0.29 is tested at the null hypothesis:
This means that [tex]\mu = 0.29, \sigma = \sqrt{0.29*0.71}[/tex]
Suppose that in a random selection of 100 colored candies, 21% of them are blue.
This means that [tex]n = 100, X = 0.21[/tex]
Value of the test statistic:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
[tex]z = \frac{0.21 - 0.29}{\frac{\sqrt{0.29*0.71}}{\sqrt{100}}}[/tex]
[tex]z = -1.76[/tex]
Pvalue of the test:
The pvalue of the test is the probability of the sample proportion differing at least 0.21 - 0.29 = 0.08 from the population proportion, which is 2 multiplied by the pvalue of Z = -1.76.
Looking at the z-table, z = -1.76 has a pvalue of 0.0392
2*0.0392 = 0.0784
The pvalue of the test is 0.0784 > 0.01, which means that at this significance level, we do not reject the null hypothesis that the percentage of blue candies is equal to 29%.
Can someone please help me I will mark u brilliant
Answer:
1 cubic inch
Step-by-step explanation:
For rectangular prism:
[tex]l = 4 \times \frac{1}{2} = 2 \: in \\ \\ w= \frac{1}{2} \: in \\ \\ h = 2 \times \frac{1}{2} = 1 \: in \\ \\ volume \: of \: prism = lbh \\ = 2 \times \frac{1}{2} \times 1 \\ = 1 \: {in}^{3} [/tex]
Answer: The volume is 1 cubic inch.
Step-by-step explanation:
Volume of 1 cube
V= l*w*h
V= 1/2*1/2*1/2
V= 1/8 or 0.125
Volume of Prism
8*1/8= 1
Alex was making pumpkin soup that called for 3 and 4/5 cups of pumpkin. If Alex makes 2 batches of soup how many cups of pumpkin will he need?
Answer:
7 and 3/5
Step-by-step explanation:
3 and 4/5 times 2 is 7 and 3/5
Write the equation in standard form. Y=x+1
A music store conducted a survey. It showed that the number of CDs purchased by a shopper decreases with the
number of songs he downloaded. What can we likely say?
Answer: there is a correlation between a number of songs downloaded. there may or may not be causation. further studies would ave to be done to determine this.
Step-by-step explanation:
Answer:
There is a correlation between number of CDs purchased and number of songs downloaded. There may or may not be causation. Further studies would have to be done to determine this.
Step-by-step explanation:
A music store conducted a survey. It showed that the number of CDs purchased by a shopper decreases with the number of songs she downloaded. What can we likely say?
Which of these situations can be modeled by an exponential function?
A) The declining population of a city if 100 people move away every year.
B) A herd of lions whose numbers triple every decade.
C) The amount of money Grant has saved up if he makes $18.50 an hour.
D) Total distance if we drive 75mph for x hours.
Answer:
B) A herd of lions whose numbers triple every decade.
Step-by-step explanation:
Situations that can be modeled by exponential functions:
A situation can be modeled by exponential functions when the change is a multiplication or a division, not a sum or subtractions.
In this question:
In option A, C and D the measures are a sum or subtractions, as the rate of change is always the same. So it rests option B as the answer, as tripling is multiplying by 3.
BRAINLIST!!!
A construction crew built 7 1/2 miles of road in 3 1/8 days.
What is the unit rate in miles per day?
Write your answer as a fraction or a mixed number in simplest form.
Answer:
If you think numbers with fractions are annoying, consider transforming the number into fractions!
Step-by-step explanation:
7 1/2 is (14+1)/2, and 3 1/8 is (24+1)/3. Not you have 15/2 miles for 25/3 days and by dividing them you get 0.9 miles a day
Someone Please help me
Answer:
B. $104.95
Step-by-step explanation:
$160.45-$55.50=$104.95
Find the length of side x in simplest radical form with a rational denominator.
This is a 30-60-90 right triangle.
In this special triangle, opposite 60 degrees = sqrt{3}. Thus, x = sqrt{3}.
What is the measure of the missing angle
Answer:
c. 42°
Step-by-step explanation:
two interior angles= one exterior angle
let x be the other interior angle
90° + x=132°
x=132-90
x=42°
find area and perimeter. plz help very important
Answer:
To find the perimeter of a rectangle, add the lengths of the rectangle's four sides. If you have only the width and the height, then you can easily find all four sides (two sides are each equal to the height and the other two sides are equal to the width). Multiply both the height and width by two and add the results.
Step-by-step explanation:
A single 6-sided die is rolled. Which BEST describes the probability of rolling a number 4 or less? 1) A ) impossible B) unlikely likely certains
Answer:
it is likely because the majority of the outcomes are in your favor
Answer:
A
Step-by-step explanation:
Impossible, did it on usatestprep
What is happening at A?
Answer:
the last one
Drag the word or expression to complete the function.
Answer:
-5 cos (2x)
Step-by-step explanation:
Reflection over x axis just means "multiply by -1" so the answer is
f(x) = 5 cos (2x)
g(x) = -5 cos (2x)
3.Construct a line perpendicular to the line given through the point P at the right
Answer:
Step-by-step explanation:
Find the mean of the data set. 5, 4, 5, 7, 7, 7, 5, 7, 6
Answer:
Mean x¯¯¯ 5.8888888888889
Median x˜ 6
Mode 7
Range 3
Minimum 4
Maximum 7
Count n 9
Sum 53
Quartiles Quartiles:
Q1 --> 5
Q2 --> 6
Q3 --> 7
Interquartile
Range IQR 2
hope i helped:) can u plz mark me brainlest
Answer:
the mean is 5.88888888889
Step-by-step explanation:
to find the mean, add all the data results together and divide by how many results you have.
for example: 5+4+5+7+7+7+5+7+6= 53
53 divided by 9= 5.88888888889
have a good day