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Question
ΔABC is isosceles with AB = AC = 7.5 cm and BC = 9 cm (see the given figure). The height AD from A to BC, is 6 cm. Find the area of ΔABC. What will be the height from C to AB i.e., CE?
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Solution
Area of triangle ABC = `1/2 xx "Base" xx "Height"`
= `1/2 xx BC xx AD`
= `1/2 xx 9 xx 6`
= 27 cm2
Area of triangle ABC = `1/2 xx "Base" xx "Height"`
= `1/2 xx AB xx CE`
`27 = 1/2 xx 7.5 xx CE`
CE = `(27 xx 2)/7.5`
CE = 7.2 cm
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