Question

X + 6y = 27
7 x - 3y = 9 ?

Answer 1

$x + 6y = 27 \\ 7x - 3y = 9 \: \: = \: \: 14x - 6y = 18 \\ 15x = 45 \\ x = \frac{45}{15} \\ x = 3 \\ 3 + 6y = 27 \\ 6y = 24 \\ y = 4$