y = ax + b
a) a = - 1/2
P = (4, -8)
y = -1/2x + b
4 = x
-8 = y
-8 = -1/2 * 4 + b
-8 = -2 + b
-6 = b
y = -1/2x - 6
b) a = 3
P = (√3, 0)
y = 3x + b
√3 = x
0 = y
0 = 3 * √3 + b
-3√3 = b
y = 3x - 3√3
c) a = 0
P = (-2, 4)
y = b
-2 = x
4 = y
4 = b
y = 4
