SOLUTION: i need you help.! can you please help me solve this equation?? the length of a rectangle is 3 inches more than its width. If the area of the rectangle is 180 square inches, wri

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Question 189087: i need you help.! can you please help me solve this equation??
the length of a rectangle is 3 inches more than its width.
If the area of the rectangle is 180 square inches, write an equation for the above situation
Found 2 solutions by checkley75, ankor@dixie-net.com:
Answer by checkley75(3666) (Show Source):
You can put this solution on YOUR website!
L=W+3
LW=180
(W+3)W=180
W^2+3W-180=0
(W+15)(W-12)=0
W-12=0
W=12 ANS. FOR THE WIDTH.
L=12+3=15 ANS. FOR THE LENGTH.
PROOF:
12*15=180
180=180

Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
the length of a rectangle is 3 inches more than its width.
If the area of the rectangle is 180 square inches, write an equation for the above situation
:
Let x = the width
:
It says,"the length of a rectangle is 3 inches more than its width." therefore:
(x+3) = the length
:
Area = Length * Width, therefore:
A = x * (x+3)
A = x^2 + 3x; is the equation
:
It says, area = 180, therefore:
x^2 + 3x = 180
:
Subtract 180 from both sides, you have a quadratic equation:
x^2 + 3x - 180 = 0
:
This will factor to:
(x + 15)(x - 12) = 0
:
We want the positive solution here:
x = + 12 is the width
then
12 + 3 = 15 is the length
:
:
Check by finding the area: 12 * 15 = 180