Which of the following functions represents a cell phone bill if there is a monthly charge of 20 dollars plus 6 cents for each minute of use?
f(x) = 20 + 0.06x
f(x) = 20 + 6x
f(x) = 20.06x

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.

10 miles

step-by-step explanation:

y = i/2 xtnop + (3i/2 tnop+ 1)

step-by-step explanation:

the picture is the step by step explanation.