Question

Solve this system of equations, then determine what y equals.

x + 5y= 7
2x + 4y = -4
A y=-18
B y=3
C y=8
D y=-8

Answer 1

2+2=4 and 4+4=8 and 8+8=16

Answer 2

`x+5y = 7~~~....(i)\\\\\\2x+4y = -4~~~.....(ii)\\\\\\\text{Multiply equation (i) by 2,}\\\\\\2x+10y = 14~~~.....(iii)\\\\\\(iii) - (ii):\\\\2x+10y-2x-4y = 14-(-4)\\\\\implies 6y = 14+4\\\\\implies 6y = 18\\\\\implies y = \frac{18}6\\\\\implies y = 3`