Question

como resolver
D x-y = 6
x+y = 7

Answer 1

$x - y = 6 \\ x + y = 7 \\ \\ x = 6 + y \\x = 6 + 0.5 \\ x = 6.5 \\ 6 + y + y = 7 \\ 2y = 7 - 6 \\ 2y = 1 \\ y = 1 \div 2 \\ y = 0.5$