An isosceles triangle has a base 22 cm long and a base angle of 72 degrees. Find its perimeter.

Answer 1

construct the right angled triangle, let the hypotenuse be h
cos 72 = 11/h
h = 11/cos72 = ....

perimeter = 22 + 2h = ....

Answer 2

The 2 unequal side if a parallelogram measure 4.8 inches and 8.3 inches, respectively. If the longer diagonal measure is 11.2 inches, find the lenght of the shorter diagonal.