Question 1081340: Trying to solve for x. The unit of measurements is in inches. I know that 1/2 the area is a 4 x 3 rectangle, or 12 square inches. The total area is 4in * x, and 3in * x. ( * is the plus sign btw, my key is not working...)Assuming the total area is 24 square inches, what would my value be for x?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! the area is a 4 x 3 rectangle, or 12 square inches. The total area is 4in * x, and 3in * x. ( * is the plus sign btw, my key is not working...)Assuming the total area is 24 square inches, what would my value be for x?
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Here's the way I understand this:
(3 + x) * (4 + x) = 24
FOIL
12 + 3x + 4x + x^2 = 24
Arrange as a quadratic equation
x^2 + 7x + 12 - 24 = 0
x^2 + 7x - 12 = 0
Use the quadratic formula a=1; b=7; c=-12
I got a positive solution of
x = 1.4244
:
:
See if that checks out
3 + 1.4244 = 4.4244
4 + 1.4244 = 5.4244
Find the area
5.4244 * 4.4244 = 23.9997 ~ 24
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