[tex]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 = \dfrac{18}6\\\\\implies y = 3[/tex]