Question

the breath of a rectangle is 8cm less than its length.if the perimeter is 60cm,find the length and breath

Answer 1

2 (l+b) = 60
2 (l + l-8)= 60
2 (2l - 8) = 60
4l - 16= 60
4l = 60
l = 15

Hence length =15 and breadth = 7

Answer 2

$let \: the \: length \: be \: x \\ and \: breadth \: be \: x - 8 \\ \\ perimeter \: of \: retangle \: = 2 (l + b) \\ \\2(x + x - 8) = 60 \\ 2(2x - 8) = 60 \\ 4x - 16= 60 \\ 4x = 60 - 16\\ x = 44 \div 4 \\ x = 11 \\ l = 11 \\ b = 6$