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Question
Area of triangle PQR is 100 cm2 (see figure). If altitude QT is 10 cm, then its base PR is ______.
Options
20 cm
15 cm
10 cm
5 cm
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Solution
Area of triangle PQR is 100 cm2 (see figure). If altitude QT is 10 cm, then its base PR is 20 cm.
Explanation:
We know that, area of triangle = `1/2` × base × height
From the question, it is given that, area of triangle PQR = 100 cm2
Height of the triangle = 10 cm = altitude
Therefore, area of triangle = `1/2` × base × height
100 = `1/2` × PR × 10
PR = `(100 xx 2)/10`
PR = `200/10`
PR = 20 cm
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