Question

7. -5a + 7 = -38
Please show your work

Answer 1

Answer:

$\boxed{\tt a=9}$

Step-by-step explanation:

We are given the equation:

$-5a+7= -38$

We want to solve for a, so we must isolate a on one side of the equation.

7 is being added to -5a. The inverse of addition is subtraction. Subtract 7 from both sides of the equation.

$-5a+7-7=-38-7$

$-5a=-38-7$

$-5a=-45$

a is being multiplied by -5. The inverse of multiplication is division. Divide both sides of the equation by -5.

$\frac{-5a}{-5} =\frac{-45}{-5}$

$a=\frac{-45}{-5}$

$a=9$

Let's check our solution. Plug 9 in for a.

$-5a+7=-38$

$-5(9)+7=-38$

$-45+7=-38$

$-38=-38$

This checks out, so we know our solution a=9 is correct.

Answer 2

-5a +7 =-38

-5a +7 (-7) = -38 (-7)

-5a= -45

-5a (÷-5)= -45 (÷-5)

a= 9