Question

A rectangular lawn has an area of 140 square yards. Its width is 6 yards less

than twice its length. Determine the length and width of the lawn. Round to
the nearest tenth if necessary

Answer 1

length : 10 yard

width: 14 yard

Explanation:

Let l be the length of the yard.

Since the width is 6 yards less than twice its length, we can say the width is 2l-6.

With width x length=area,

l (2l -6) = 140

2l^2 - 6l = 140

2l^2 - 6l - 140 = 0

Using the quadratic formula,

we can determine l = 10 or -7

since the length should not be negative,

the length is 10 yard.

Now substitute l=10 into 2l-6.

width = 2(10)-6

= 14 yard