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A trapezoid has an area of 341 square miles.

One base is 8 miles long.

The height measures 22 miles.

What is the length of the other base ?

$\begin{array}{|rcll|} \hline A &=& \left(\frac{x+8}{2} \right) \cdot 22 \\ 341 &=& \left(\frac{x+8}{2} \right) \cdot 22 \\ 341 &=& (x+8) \cdot 11 \quad &| \quad : 11 \\ 31 &=& x+8 \quad &| \quad - 8 \\ 31-8 &=& x \\ 23 &=& x \\ \hline \end{array}$

The other base is 23 miles long.