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A carpenter is making a rectangular form for a concrete pad she wants the length of the path to be 11 feet more than the width of the bed the area of the concrete pad must be 80 ft.² write the quadratic equation that will be used to find the dimensions of the pad

Respuesta :

Lanuel

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.