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The area of a trapezium is 180 cm2 and its height is 9 cm. If one of the parallel sides is longer than the other by 6 cm, find the two parallel sides. |
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Answer» Given Let length of first parallel side X Length of other parallel side is X + 6 Area of trapezium= 180 cm2 Let Height (h) = 9 cm We know that area of trapezium is \(\frac{1}{2}\)× (sum of parallel sides) × height Therefore Area of trapezium is \(\frac{1}{2}\)× (X + 6 +X) × 9 = 180 cm2. \(\therefore\) \(\frac{1}{2}\)× (X + 6 +X) × 9 =180 ⇒ \(\frac{1}{2}\)× (2X + 6) × 9 =180 ⇒ 2X + 6 = \(\frac{180}{9}\times2\) ⇒ 2X + 6 = 40 ⇒ 2X = 40 – 6 = 34 ⇒ X = 17 ∴ Length of the parallel sides is X = 17 cm and X + 6 = 17 + 6 = 23 cm. Therefore lengths of the parallel sides are 17 cm, 23 cm. |
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