If the diagonal of a rectangle is 39cm long and its perimeter is 86 cm. Find the area of the rectang

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19 Oct 2020 Area

If the diagonal of a rectangle is 39cm long and its perimeter is 86 cm. Find the area of the rectangle in sq. cm.

OPtion

1) 164
2) 228
3) 328
4) 264
5) 364
6) 128
7) 174
8) 184
9) 154
10) None of these

Solution

Let length = x and breadth = y then

2(x+y) = 86 => x+y = 43
x²+y² = 39² = 1521
now (x+y)² = 43² = 1849
=> x²+y²+2xy= 1849
=> 1521 + 2xy = 1849
=> xy = 164
area = xy = 164 sq.cm

Option 1)

Correct Option: 1 Best Solution (0)