Help! I just don't understand

$71

Step-by-step explanation:

Since x denotes the number of miles and we know that the car rode 100 miles, this means that x=100, and when we plug this in, we get C(x) = 0.5* 100 + 21 = 50 + 21 = $71. Hope this helps!

C(100) = 71

Step-by-step explanation:

C(x) = .5x+21

Let x= 100

C(100) = .5(100)+21

         = 50+21

        = 71

false

step-by-step explanation:

false.   two legs of the trapezoid would be congruent, but the other two would not.   were all the legs congruent, then we'd have a square; were the 2 shorter sides congruent and the 2 longer sides also congruent, we'd have a rectangle.