SOLUTION: Given the diagram below, find the dimensions of the rectangle if the area is 128 square feet. Rectangle Area=(x-1)(x+7) I have no idea how to do this and if you could please

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Question 1078770: Given the diagram below, find the dimensions of the rectangle if the area is 128 square feet.
Rectangle Area=(x-1)(x+7)
I have no idea how to do this and if you could please explain the steps that would be awesome!
Thank You!!!
Found 2 solutions by stanbon, MathTherapy:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Given the diagram below, find the dimensions of the rectangle if the area is 128 square feet.
Rectangle Area=(x-1)(x+7)
------
x^2 + 6x - 7 = 128
-----
x^2 + 6x - 135 = 0
-----
(x-9)(x+15) = 0
x = 9
---
Dimensions::
x-1 = 10 ft.
x+7 = 16 ft.
--------------------
Cheers,
Stan H.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

Given the diagram below, find the dimensions of the rectangle if the area is 128 square feet.
Rectangle Area=(x-1)(x+7)
I have no idea how to do this and if you could please explain the steps that would be awesome!
Thank You!!!
Dimensions: highlight_green%28matrix%281%2C5%2C+8%2C+feet%2C+by%2C+16%2C+feet%29%29