Question

The sides of a triangle taken in order are each 3cm longer than the preceding sides . If the perimeter of a triangle is 81 cm . Find the length of its sides.

Answer 1

let the sides be x, x+3 , x+6

81 = x + x+3 + x+6
81 = 3x + 9
72 = 3x
72/3 = x
x = 24


so the sides of triangle are 24cm, 27cm & 30cm

Answer 2

$first \: side = x \\2nd \: side = x + 3 \\ 3side = x + 3 + 3 = x + 6 \\ perimeter = 81cm \\ 81 = x + x + 3 + x + 6 \\ 81 = x + x + x + 3 + 6 \\ 81 = 3x + 9 \\ 81 - 9 = 3x \\ 72 = 3x \\ \frac{72}{3} = x \\ 24 = x \\ 1side = x = 24 \\ 2side = x + 3 = 24 + 3 = 27 \\ 3side = x + 3 + 3 = 24 + 3 + 3 = 30 \\ so \: 24 + 27 + 30 = 81cm$
this is ur answer