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3 years ago

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The area of a trapezoid is 132 cm 2. The height is 12cm and the length of one of the parallel sides is 9cm. Find the length of t

he second parallel side. Express your answer as a simplified fraction or a decimal rounded to two places.

1 answer:

zhuklara [117]3 years ago

7 0

Answer

Find out the length of the second parallel side.

To prove

Formula

$Area\ of\ Trapezoid = \frac{(a + b)\times h}{2}$

Where a , b are the parallel sides of trapezoid and h is the height of the trapezoid.

As given

The area of a trapezoid is 132 cm².

The height is 12cm and the length of one of the parallel sides is 9cm.

Here h = 12cm

a = 9cm

Put in the formula

$132= \frac{(9 + b)\times 12}{2}$

132 × 2 = 9 × 12 + 12b

264 = 108 + 12b

264 - 108 = 12b

156 = 12b

$b = \frac{156}{12}$

b = 13cm

Therefore the length of the second parallel side is 13cm.

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Answer:

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Step-by-step explanation:

The diagram illustrating the question is shown on the first uploaded image

From the question we are told that

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Generally according to Sine Rule

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