Your answer is:
(125 - 8x^3) / (25 + 10x + 4x^2) = - ((2x - 5) * (4x^2 + 10x + 25)) / (4x^2 + 10x + 25) = - (2x - 5) = - 2x + 5
The correct result would be - 2x + 5.
I think is 3 and 2/3 (I hope I got it right)
27)
Equation of the existing water pipe's line
a) slope, m = rise / run = Δy / Δx = 3/2
b) y-intercept, b = 3
equation: y = mx + b = (3/2)x + 3
Equation of the new water pipe's line
slope, m = - 1 / (slope of the perpendicular line) = - 1 / (3/2) = - 2/3
point (0,2)
=> y - 2 = (-2/3) (x - 0) => y = (-2/3)x + 2 <---- equation of the new pipe
28)
two parallel lines have the same slope =>
slope, m = rise / run = Δy / Δx = [4 - 0] / [11 - 8] = 4 / 3
point (4,5) => y - 5 = (4/3) (x - 4)
=> y = (4/3)x - 16/3 + 5 = (4/3)x - 1/3
y = (4/3)x - 1/3 <--- equation of the new bike path
