Solve. For Exercises 83 and $84,$ see the second Concept Check in this section, for Exercises 85 and $86,$ see the third Concept Check.
A parallelogram has an area of $\frac{x^{2}+x-2}{x^{3}}$ square feet and a height of $\frac{x^{2}}{x-1}$ feet. Express the length of its base as a rational expression in $x .$ (Hint: since $A=b \cdot h, b=\frac{A}{h}$ or $b=A \div h .)$
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