Question

The width of a rectangle is 7 feet less than its length. If the area of the rectangle is 170 square feet, then find the length and width.

Answer 1

l=x
b=x-7

Area=l×b

170=x(x-7)
170=x²-7x
x²-7x-170=0
x²-17x+10x-170=0
x(x-17)+10(x-17)=0
(x-17)(x+10)=0

x=17


Length =17 feet
width=17-7=10 feet

Answer 2

Dear Student,

● Answer -

l = 17 feet

b = 10 feet

● Explanation -

Suppose l and b be length and breadth of rectangle.

b = l - 7

Area of rectangle is calculated by -

A = l × b

A = l × (l-7)

170 = l^2 - 7l

l^2 - 7l - 170 = 0

Solving this equation,

l = 17 feet

Now, width be -

b = l - 7

b = 17 - 7

b = 10 feet

Hence, length and width are 17 feet and 10 feet respectively.

Hope this helps you...