The function a(b) relates the area of a trapezoid with a given height of 10 and one base length of 7 with the length of its other base.
It takes as input the other base value, and returns as output the area of the
trapezoid.
a(b)=10•b+7/2
Which equation below represents the inverse function b(a), which takes the
trapezoid's area as input and returns as output the length of the other base?

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.

a

step-by-step explanation: