Question

what is the equation of the line that passes though the points (-3,4) and (-9,6)

Answer 1

The equation for a straight line is

y = mx + b
Substitute 4 for y and -3 for m in the equation to obtain equation #1. Do the same, substituting 6 for y and -9 for x to obtain equation #2. Then solve the two equations simultaneously to obtain x and b.