Question

If x - y = 6, x2 + y2 = 180, find (x, y).

Answer 1

$\huge\tt\colorbox{lime}{Answer}$

$x - y = 6 \\ {x}^{2} + {y}^{2} = 180 \\ \\ {a}^{2} + {b}^{2} = (a + b)(a - b) \\ \\ {x}^{2} + {y}^{2} = (x + y)(x - y) \\ 180 = (x + y) \times 6 \\ x + y = \frac{180}{6} \\ x + y = 30$