Question

What mistake did this student make?

1. They should have multiplied the second equation by 3

2. They should have multiplied the first equation by 2

3. x = -2 not 2

4. y = 5 not -5

Answer 1

x=-2 not 2.


Step-by-step explanation:

x-2y=12
-3x+y=-1
x-2y=12
2(-3x+y)=-1
x-2y=12
-6x+2y=-2
-5x=10
5x/-5=10/-5
x=-2