Question

2x + y = 20
6x - 5y = 12

Answer 1

x=7, y=6

Explanation:

we expand the first formula by 5.

5(2x+y) = 20x5

10x + 5y= 100

then we add the two formulas together.

10x+5y+6x-5y = 100+12

since the 5y can be cancelled out, it is much easier.

16x = 112

x=7

now we can put x=2 into the first formula.

2x7+y =20

y=6

Answer 2

x=7, y=6

Explanation: