Hello!
Since it has to go through the point (3,1) we can put 3 in for x and see if we get y = 1
y = -2(3) + 7
y = -6 + 7
y = 1
So it can be the first one
y = -2(3) + 6
y = -6 + 6
y = 0
It can not be the second
y = -2(3) - 2
y = -6 - 2
y = -8
It can not be the third one
y = 3(3) - 8
y = 9 - 8
y = 1
So it can be the first one or the second one
We can just look at both of the equations
3x has a steeper slope than -2x so eventually they will cross so they are not parallel
So the answer is -2x + 7
Hope this help!
