ShmoopTube

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Here’s an unshmoopy question you’ll find on an exam somewhere in life…

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What is the area of the figure below in square centimeters? 

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And here are the potential answers...

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This question is testing our ability to figure out how to calculate the area of the triangle.

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The square and rectangle should be easy enough.

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If not, we’re in deep doo-doo.

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But… just to get those out of the way, we have 6 times 6 – base times height – as

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the area for the square, or 36 square centimeters.

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And the rectangle has an area of 9 times 3 or 27.

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So we know we already have 36 plus 27 or 63 square centimeters before

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we even begin calculating the area of the triangle.

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This lets us cross off A and B as possible answers because it’s a pretty safe bet that

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the triangle’s area is much more than just...1.

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The triangle has base 3 and height 6.

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Whoa. How’d we get there?

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Well, we know that THIS line is 6 centimeters because it’s the length of the rectangle…

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9… minus 3.

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Same deal with the square… 6, the length of the square, minus 3… is 3.

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So the base of the triangle is 3 and the height is 6. We can plug these numbers into the formula

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one half times base times height and we get this:

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Which calculates to one half of 18 or... 9.

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So add the 9 square centimeters of the triangle’s area to the square and rectangle and we have 72.

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The answer is C.

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As in… “Centimeters kick inches’ butt.”

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