मराठी

If the diagonal d of a quadrilateral is doubled and the heights h1 and h2 falling on d are halved, then the area of quadrilateral is ______. - Mathematics

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प्रश्न

If the diagonal d of a quadrilateral is doubled and the heights h1 and h2 falling on d are halved, then the area of quadrilateral is ______.

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उत्तर

If the diagonal d of a quadrilateral is doubled and the heights h1 and h2 falling on d are halved, then the area of quadrilateral is `underlinebb(1/2(h_1 + h_2)d)`.

Explanation:

Let ABCD be a quadrilateral, where h1 and h2 are altitudes on the diagonal BD = d.

Then, area of quadrilateral `ABCD = 1/2(h_1 + h_2) xx BD`

If altitudes are halved and the diagonal is doubled, then

Area of quadrilateral `ABCD = 1/2(h_1/2 + h_2/2) xx 2d`

= `1/2((h_1 + h_2)/2) xx 2d`

= `1/2(h_1 + h_2) xx d`

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पाठ 11: Mensuration - Exercise [पृष्ठ ३५०]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 8
पाठ 11 Mensuration
Exercise | Q 38. | पृष्ठ ३५०

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