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Write a quadratic function f(x) for the area of a rectangle length x+5 width 3x-7

User Tkowal
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1 Answer

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The area of a rectangle is the product of its length and width.

l=x+5 \\ w=3x-7 \\ \\ A=lw=(x+5)(3x-7)=3x^2-7x+15x-35=3x^2+8x-35 \\ \\ \boxed{f(x)=3x^2+8x-35}
User Michael Langhammer
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