Question
The sum of the length, breadth, and height of a cuboid
is 30 cm. If the length of the diagonal is 17 cm, find the total surface area of the cuboid.Solution
l+ b+ h = 30 Diagonal =17 Diagonal = β l2+b2+h2 (l+ b+ h)2 = l2+b2+h2+ 2(l b+ b h +h l) (30)2 = (17)2 +2(l b+ b h +h l) 900 = 289 +2(l b+ b h +h l) 2(l b+ b h +h l) = 900-289=611 2(l b+ b h +h l) =611 Total surface area of cuboid =611 cm2
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