Find the length of side AD

Question

The perimeter of the rectangle below is 168 units. Find the length of side AD. Write your answer without variables.

Side AB: 5z + 3

Side CB: 4 z

Side AD: ?

Answer 1

Perimeter = 168 = 2(L+W)= 2(5z+3 +4z)

84 = 9z +3

9z = 81

z = 81/9 = 9

5z+3 = 5(9)+3= 48 = Length

4z = 4(9) = 36 = Width

2(48+36) = 2(84) = 168 = Perimeter

side AD? If it's a rectangle, then AD = either 36 or 48

or

are you using D as the Diagonal? AD = the hypotenuse of a right triangle with sides 36 and 48

then

AD = 60

=sqr(36^2+48^2)