She should multiply y = x - 2 by -4...that way one x will be -4x and the other will be 4x and they will cancel out when added.
answer is -4
<span>A. the area of the circular base multiplied by the height of the cylinder B. the circumference of the circular base multiplied by the height of the cylinder C. the sum of the areas of the two circular bases multiplied by the height of the cylinder D.</span>
6.b
7.d
8.a
9.c
see attached image. sorry that’s it’s all jumbled up weird, i could only figure out how to put them all together using photoshop. hope these help you out :))
Using a system of equations, it is found that David is 12 years old.
<h3>What is a system of equations?</h3>
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
The variables are given as follows:
- Variable z: Rebecca's age.
David is three times younger than the dad and twice as old as Rebecca, then:
Rebecca is 30 years younger than the dad, hence:
z = y - 30.
Then, since x = 2z and z = y - 30 and y = 3x, we solve for x to find David's age.
x = 2(y - 30)
x = 2(3x - 30)
x = 6x - 60
5x = 60
x = 60/5
x = 12.
David is 12 years old.
More can be learned about a system of equations at brainly.com/question/24342899
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