SOLUTION: A 16 by 20-inch mounting board is used to mount a photograph. How wide a uniform border is needed if the photograph occupies 3/5 of the area of the mounting board?

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons -> SOLUTION: A 16 by 20-inch mounting board is used to mount a photograph. How wide a uniform border is needed if the photograph occupies 3/5 of the area of the mounting board?      Log On


   

Question 350353: A 16 by 20-inch mounting board is used to mount a photograph. How wide a uniform border is needed if the photograph occupies 3/5 of the area of the mounting board?
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Let represent the width of the uniform border. Then the dimensions of the picture must be and . The area of the overall picture and mounting board is in2 -- of which is 1920 in2.

So:



Multiply out the binomials, collect terms, put the equation into standard quadratic form, and then solve for , the width of the border.

John

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