Question

A cross-section of an irrigation canal is a parabola. If the surface of the water is 34 ft wide and the canal is deep at the center, how deep is it 9 ft from the edge?

Answer 1

Answer:

6.41 ft

Step-by-step explanation:

Equation is y=ax^2

y=15

x=16.5

15=a(16.5)^2

a=0.055

So, to get depth at 4 ft from edge, I assume my new x value is 12.5.

Derived from 16.5 - 4 = 12.5

So:

y= 0.055 * (12.5)^2

y = 8.59

To get depth, I assume subtract from center depth of 15ft.

15ft - 8.59ft = 6.41ft

Answer is 6.41ft.