Chapter 14.2, Problem 12PPS

To determine

To simplify expression and calculate perimeter of figure.

Answer to Problem 12PPS

Expression= $20x-5$

Perimeter=21 cm

Explanation of Solution

Given information:

Base = $(9x-4)cm$

Height = $(9x-4)cm$

Hypotenuse = $(2x+3)$ $cm$

Formula used: perimeter of triangle=sum of all sides

Calculation:

According to question,

Perimeter=base + height+ hypotenuse

Substituting the values,

  $\begin{array}{l}=(9x-4)+(9x-4)+(2x+3)\\ =9x-4+9x-4+2x+3\\ =18x-8+2x+3\\ =20x-5\end{array}$

Putting x =0.8

  = $20(0.8)-5$

  =21cm

Perimeter is 21 cm