How do you find the dimensions that has something to do with quadratic equations?

Question

kirbykirby · Answer

Dimensions of what exactly? The question is a little vague. Do you have more context for this?

mopsy510 · Answer

I'll type the whole problem

mopsy510 · Answer

A rectangular painting has dimensions "x" and "x+10". The painting is in a frame 2 in. wide. The total area of the picture and the frame is 900 in. squared. What are the dimensions of the painting?

mopsy510 · Answer

Hello?

kirbykirby · Answer

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So since along each side, you have (2+2)=4 inches LESS for the painting, each side will have dimensions of the painting would be "x-4" and "x+6" (since you are doing x+10-4)

So the area = side*side = (x-4)(x+6)
We know the are is 900
so, 900 = (x-4)(x+6) = $x^2+6x-4x-24=x^2+2x-24$

so, $0=x^2+2x-924$ ... and use the quadratic equation to find x