Question

A student is trying to solve the system of two equations given below:

Equation P: x + y = 8
Equation Q: 2x + 5y = 24

Which of the following steps can be used to eliminate the x term?

A. 2(x + y = 8)

B. -2(x + y = 8)

C. -1(2x + 5y = 24)

D. -2(2x + 5y =24)

Answer 1

A

Explanation:

Answer 2

A. 2(x + y = 8)
Once you do that with Equation P, you can do the following:

2x + 2y = 16
(2x + 2y) - (2x + 5y) = 16 - 24 ( modified Equation P minus Equation Q )
2x - 2x + 2y - 5y = 16 - 24
-3y = -8
Magic. x has been eliminated.