geometry
posted by Veronica on .
ABCD is an isosceles trapezoid with a height of 4 inches and bases of 10 and 12 inches .What is the perimeter of this trapezoid in inches and feet . HINT:Only the bottom of the entire figure is 16 inches long, not the top

First, we draw the trapezoid with the long base on the bottom. Using dotted lines, we draw 2 altitudes forming 2
congruent rt. triangles and a rectangle.
AE=ED = (ADBC) / 2 = (1210)/2 = 1in =
hor. sides of rt. triangles.
AB = CD = sqrt(1^2+4^2) = sqrt17 =
4.1in. = Length of nonparallel sides.
P = 4.1 + 10 + 4.1 + 12 = 30.2in.