An angle bisector ac divides a trapezoid abcd into two similar triangles △abc and △acd. find the perimeter of this trapezoid if the leg ab=9 cm and the leg cd=12 cm.

42 cm

Step-by-step explanation:

Given: An angle bisector AC divides a trapezoid ABCD into two similar triangles △ABC and △ACD.

⇒ All the corresponding angles in both triangles are congruent.

Since AC=AC [ reflexive property]

⇒ △ABC ≅△ADC [By AAS congruence theorem]

⇒AB=AD= 9 cm and BC=CD=12 cm [ By CPCTC]

Now, Perimeter of trapezoid =AB+BC+CD+AD

Perimeter of trapezoid

10 cm

step-by-step explanation:

if the polygon is a rectangle, then the perimeter is x+x+y+y. using the values that you gave, the perimeter is 3+3+2+2=10cm.

step-by-step explanation: