Question

A rectangle has an area of 171 square meters. Its width is ten meters less than the length. Find the measures of the length and width of the rectangle.

Answer 1

Step-by-step explanation:

The area of a rectangle is 171 m²

Let l is the length and b is the width of the rectangle

It width is 10 m less than the length. So,

b = l-10 ...(1)

Area of a rectangle is given by :

$A=l\times b\\\\171=l(l-10)\\\\l^2-10l=171\\\\l^2-10l-171=0\\\\l^2-19l+9l-171=0\\\\\text{taking common together}\\\\l(l-19)+9(l-19)=0\\\\(l-9)(l-19)=0$

or

l = 9 m or l = 19 m

If l = 9 m,

b = 9-10 = -1 m (can't be possible)

If l = 19 m

b = 19-10 = 9 m

So, the length an the breadth of the rectangle is 19 m and 9 m respectively.