word problem

the area is 315 square centimeters

Any day now

Area of a rectangle=W x L

Perimeter of rectangle=2 [W +L]=96 cm

5/[5+7] x 96 =40/2 = 20 cm-the width of the rectangle

7/[5+7] x 96 =56/2 = 28 cm-the length of the rectangle

Area=20 x 28 =560 cm^2

Here's another approach........let the shorter side of the rectangle = x.......then the longer side = (7/5)x

So......the perimeter is given by :

2x + 2(7/5)x = 96     multiply through by 5

10x + 14x  = 480

24x = 480

x = 20     and (7/5)x = 28

So....the area = 20 * 28 =  560cm^2