SOLUTION: If the area of a rectangle can be expressed as x2+x-56 cm2, what is the smallest possible value of x? Explain.

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Question 562968: If the area of a rectangle can be expressed as x2+x-56 cm2, what is the smallest possible value of x? Explain.
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
x^2 + x - 56 = 0 when x = 7 or x = -8 (you can check by factoring). It can be shown that x^2 + x - 56 is positive when x > 7 or x < -8. Hence there is no smallest possible value of x (since x can go to negative infinity and the area is still positive). Note that the dimensions themselves do not necessarily have to be polynomials.