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Question
In a rectangle ABCD, AB = 7 cm and AD = 25 cm. Find the height of a triangle whose base is AB and whose area is two times the area of the rectangle ABCD.
Solution
Area of rectangle ABCD = AB x AD = 7 x 25 = 175cm2
Area of triangle whose base is AB = `(1)/(2) xx "AB" xx "Height" = (1)/(2) xx 7 xx "Height"`
Now,
Area of triangle whose base is AB = 2 x Area of rectangle ABCD
⇒ `(1)/(2) xx 7 xx "Height"` = 175
⇒ Height
= `(175 xx 2)/(7)`
= 50cm.
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