first we find the slope by using the slope formula : (y2 - y1) / (x2 - x1)
slope = (y2 - y1) / (x2 - x1)
(0,7)....x1 = 0 and y1 = 7
(8,-2)...x2 = 8 and y2 = -2
now sub...pay attention to ur signs
slope = (-2 - 7) / (8 - 0) = -9/8
now we use y = mx + b
slope(m) = -9/8
u can use either of ur points...(0,7)...x = 0 and y = 7
now sub into ur formula and find b, the y int
7 = -9/8(0) + b
7 = b
so ur equation is : y = -9/8x + 7 <==