Answer:
y=-9x+54
Step-by-step explanation:
you will use the eqaution y-y1=m(x-x1)
m = -9 the slope and plug in ur x and y points
so it be y - (-9) = -9(x-7)
distribute the -9 to get ---> y + 9 = -9x + 63
subtract 9 from both sides
y = -9x + 54