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Question
The diagonal of a rectangular board is 1 m and its length is 96 cm. Find the area of the board.
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Solution
Length of diagonal (AB) = 96 cm
Diagonal (AC) = 1 m = 100 cm
In right-angled triangle ABC,
By Applying Pythagoras Theorem,
(AC)2 = (AB)2 + (BC)2
= (100)2 = (96)2 + BC2
10000 = 9216 = BC2
10000 − 9216 = BC2
`sqrt784` = BC
∴ BC = 28 cm
Area of the rectangular board
= l × b or AB × BC
= 96 × 28
= 2688 cm2
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