Question

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

Equation P: y + z = 6
Equation Q: 3y + 4z = 1

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

(y + z = 6) ⋅ 4
(3y + 4z = 1) ⋅ 4
(y + z = 6) ⋅ −3
(3y + 4z = 1) ⋅ 3

Answer 1

The second and fourth options are out because they're multiplying the larger variables. Can you run through the first and third yourself?

Answer 2

I can try

Answer 3

Do you want me to set the equations up for you?

Answer 4

I think I got it

Answer 5

Wait, would it be c ?

Answer 6

Yes, it would be c. What was your reasoning for choosing c?

Answer 7

Because in equation Q it starts with 3 and I remember something about a negative sign if that makes any sense

Answer 8

So you just thought of how -3 + 3 = 0 via the addition method?

Answer 9

I think

Answer 10

Well as long as you understand it. If you ever need help with these kinds of problems, just ask. practice is the best way to understand.

Answer 11

Okay thank you

Answer 12

No problem :)