Question

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

Equation A: x + z = 6
Equation B: 4x + 5z = 1

Which of these is a possible step used in eliminating the z-term?

Multiply equation B by 5.

Multiply equation A by –5.

Multiply equation A by 4.

Multiply equation B by 4

Answer 1

Multiply equation A by -5.

Once this is done you can add equation A to equation B and see that we are adding -5z to 5z, resulting in the value 0.