Question

The perimeter of the rectangle below is 74 units. Find the length of side AD.Write your answer without variables.D32-3A2zCBAD =

Answer 1

The perimeter of a figure is the sum of lengths of the sides.

For the given rectangle the perimeter is:

`\begin{gathered} P=2(3z-3)+2(2z) \\ \\ 74=2(3z-3)+2(2z) \end{gathered}`

Use the equation above to solve z:

`\begin{gathered} 74=6z-6+4z \\ 74=10z-6 \\ 74+6=10z-6+6 \\ 80=10z \\ (80)/(10)=(10z)/(10) \\ \\ 8=z \\ \\ z=8 \end{gathered}`

Use the vlue of z to find the length of AD:

`\begin{gathered} AD=3z-3 \\ AD=3(8)-3 \\ AD=24-3 \\ AD=21 \end{gathered}`

Then, the length of side AD is 21 units