The first thing we must do for this case, is to define a variable.
We have then:
w: width of the rectangle.
By definition, the area of the rectangle is the product of the length by the width.
We have then:
[tex]A = (w) * (2w + 7)
[/tex]
Substituting the value of the area we have:
[tex]99 = (w) * (2w + 7)
[/tex]
Rewriting the polynomial:
[tex]2w ^ 2 + 7w - 99 = 0
[/tex]
When factoring we have:
[tex](w + 9) (2w-11) = 0
[/tex]
Taking the positive root we have:
[tex]2w-11 = 0
2w = 11
w = 11/2
w = 5.5 yd[/tex]
Then, the length of the rectangle is:
[tex]2w + 7 = 2 (5.5) + 7 = 11 + 7 = 18 yd
[/tex]
Answer:
the dimensions of the rectangle are:
width = 5.5 yd
Long = 18 yd