Answer:
The equation for the parallel line is: y = -4x - 20
The equation for the perpendicular line is: y = 1/4x + 11/2
Step-by-step explanation:
The given point is: (-6, 4)
The given equation is:
y = -4x + 8, note the slope m = -4.
A parallel line has the same slope. Use the point slope and substitute:
y - y1 = m(x - x1)
y - 4 = -4(x - (-6))
y - 4 = -4(x + 6)
y - 4 = -4x - 24
y = -4x - 20
Proof - find f(x) when x = -6:
f(x) = -4x - 20
f(-6) = -4(-6) - 20
f(-6) = 24 - 20 = 4, so the point is (-6, 4)
A perpendicular line has a slope that is negative and inverted so m = 1/4.
y - y1 = m(x - x1)
y - 4 = 1/4(x - (-6))
y - 4 = 1/4(x + 6)
y - 4 = 1/4x + 6/4
y - 4 = 1/4x + 3/2
y = 1/4x + 3/2 + 4
y = 1/4x + 3/2 + 8/2
y = 1/4x + 11/2
Proof - find f(x) when x = -6:
f(x) = 1/4x + 11/2
f(-6) = 1/4(-6) + 11/2
= -6/4 + 11/2
= -3/2 + 11/2
= 8/2 = 4, giving the point (-6, 4)
