Chapter 14.2, Problem 3GP

i.

To determine

Write and simplify expression

Answer to Problem 3GP

  $6x^2-8x$

Explanation of Solution

Given:

Length= $(x^2-5x)$

Breadth= $(2x^2+x)$

Formula Used:

Perimeter= 2( l+ b )

Calculation:

As per the given problem,

Perimeter= 2( l+ b )

  $\begin{array}{l}=2(x^2-5x+2x^2+x)\\ =2(3x^2-4x)\\ =6x^2-8x\end{array}$

Expression is $6x^2-8x$

ii.

To determine

  $131.76$

Explanation of Solution

Given:

  $x$ =5.4 units

Calculation:

From (i)

Perimeter= $6x^2-8x$

Substituting value of x ,

  $\begin{array}{l}$ =6{(5.4)}^2-8(5.4)$=131.76\end{array}$

Perimeter is 131.76 units