SOLUTION: The length of a photograph is 1cm less than twice the width. The area is 23cm squared. Find the dimensions of the photograph.

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: The length of a photograph is 1cm less than twice the width. The area is 23cm squared. Find the dimensions of the photograph.      Log On


   

Question 132631: The length of a photograph is 1cm less than twice the width. The area is 23cm squared. Find the dimensions of the photograph.
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
L=2W-1
(2W-1)W=23
2W^2-W-23=0
USING THE QUADRATIC EQUATION:x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ WE GET:
W=(1+-SQRT[-1^2-4*2*-23 ])/2*2
W=(1+-SQRT[1+184])/4
W=(1+-SQRT185)/4
W=(1+-13.6)/4
W=(1+13.6)/4
W=14.6/4
W=3.65 ANSWER FOR THE WIDTH.
L=2*3.65-1
L=7.3-1
W=6.3 ANSWER FOR THE LENGTH.
PROOF:
3.65*6.3=23
23=23