Chapter 13, Problem 12STP

To determine

Find the effect on the area and perimeter of the rectangle , after doubling the dimensions of the rectangle.

Answer to Problem 12STP

Area becomes 4 times and the perimeter doubles.

Explanation of Solution

Given:

Calculation:

We can check it on general basis.

Given the length of rectangle = l = 3.9 yd

Width of rectangle = w = 5 yd

Perimeter of rectangle = $P_1=2(l+w)$

Area of rectangle = $A_1=lw$

Now, doubling the length and width becomes 2l and 2w respectively.

Area = $A_2=(2l)(2w)=4lw=4A_1$

Perimeter = $P_2=2(2l+2w)=2\left[2(l+w)\right]=2P_1$

Hence , the effect on the area and perimeter of the rectangle , after doubling the dimensions of the rectangle is that area becomes 4 times and the perimeter doubles.