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If the area of a trapezoid is 46 sq. cm. and its height is 4 cm. Find the shorter base if itslonger base is 15 cm.

If the area of a trapezoid is 46 sq. cm. and its height is 4 cm. Find the shorter-example-1
User Alexander Pivovarov
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1 Answer

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We are given the following information about a trapezoid.

Area = 46 sq cm

Height = 4 cm

Longer base = 15 cm

We are asked to find the shorter base of the trapezoid.

Recall that the area of a trapezoid is given by


A=(a+b)/(2)\cdot h

Let us substitute the given values and solve for the shorter side of the trapezoid.


\begin{gathered} 46=((a+15)/(2))\cdot4 \\ 2\cdot46=(a+15)\cdot4 \\ 92=(a+15)\cdot4 \\ (92)/(4)=a+15 \\ 23=a+15 \\ a=23-15 \\ a=8\; cm \end{gathered}

Therefore, the shorter base of the trapezoid is 8 cm