Question

The sum of two number. Is 35 and their difference is 9 find the number

Answer 1

let the nos be x and y
x+y=35(i)
x-y=9(ii)

$x + y = 35$
$y = 35 - x$
$x - y = 9$
$x - (35 - x) = 9$
$x - 35 + x = 9$
$2x - 35 = 9$
$2x = 9 + 35$
$x = \frac{44}{2}$
$x = 22$
$y = 35 - x = 35 - 22 = 13$