the way i do is changing to slope-intercept.
a is y=4x-1
b is y=-4x+1
c is y=1/4(x)+13/4
d is y=4x+7
change in x is 2, change in y is 8. 8/2 is slope of 4. That eliminates b and c.
take one of them, in this case (-1, 3). multiply x by the slope, making -4. the number you have to add (b) is the intercept. b is 7, making the answer D
