SOLUTION: W x (L=9) = 36 2 length is 9 inches greater than the width area 36in2. Can you please break down how this is done (the formula). Thank you

Algebra ->  Rectangles -> SOLUTION: W x (L=9) = 36 2 length is 9 inches greater than the width area 36in2. Can you please break down how this is done (the formula). Thank you      Log On


   

Question 104654This question is from textbook
: W x (L=9) = 36 2
length is 9 inches greater than the width area 36in2.
Can you please break down how this is done (the formula).
Thank you This question is from textbook

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
The area of a rectangle is equal to A=L*W.
The area of your rectangle is 36 sq.inches.
Your first equation is
1. A=LW=36
You say that the length is 9 inches greater than the width, or
2.L=9%2BW
Substitute your equation (2) into (1) and solve for W.
LW=36
%289%2BW%29W=36
9W%2BW%5E2=36 Distributive property.
W%5E2%2B9W-36=0 Additive inverse of 36.
%28W%2B12%29%28W-3%29=0 Factor the quadratic equation.
Solutions are
W=-12, W=3.
Since a negative width does not make sense, we throw out that solution.
W=3 inches
L=9%2BW
L=9%2B3
L=12 inches