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

Answer: B

Explanation:

When you distribute the number to the equation you want to be able to eliminate a variable when you add.

a. not right you get 2x for your first term if you added it to the next equation you get 4x which does not eliminate x

b. is right, you get -2x +2x = 0 this is what you want

c. not right, you get -2x but added to the first -2x+x
`\\eq` 0

d. not right -4x +x
`\\eq` 0