Answer:
Length = 16 or -5 feet.
Width = 5 or -16 feet.
Step-by-step explanation:
Let the length of the concrete pad = l
Let the width of the concrete pad = w
Given the following data;
Area of concrete pad, a = 80ft²
Translating the word problem into an algebraic equation, we have;
[tex] l = 11 + w[/tex]
We know that, the area of rectangle, A = length * width
[tex] A = l*w[/tex]
Substituting the values into the equation, we have;
[tex] 80 = (11 + w)w[/tex]
Expanding the bracket, we have;
[tex] 80 = 11w + w^{2}[/tex]
[tex] w^{2} + 11w - 80 = 0[/tex]
*Solving the quadratic equation by using factorization method*
[tex] w^{2} + 16w - 5w - 80 = 0[/tex]
[tex] w(w + 16) - 5(w + 16) = 0[/tex]
[tex] (w - 5)(w + 16) = 0 [/tex]
Width, w = 5 feet or w = -16 feet.
Therefore, the width of the concrete pad is 5 feet or -16 feet.
To find its length, l;
[tex] l = 11 + w[/tex]
When w = 5 feet
[tex] l = 11 + 5[/tex]
Length, l = 16 feet
When w = - 16 feet
[tex] l = 11 + (-16)[/tex]
[tex] l = 11 - 16[/tex]
Length, l = -5 feet.
Hence, the dimensions of the concrete pad is 16 by 5 feet or -5 by -16 feet.