Question

x–3y=4 2x+y=15 метод сложение

Answer 1

x–3y=4
2x+y=15

2x–6y=8
2x+y=15

2x–6y-(2x+y)=8-15
2x-6y-2x-y= -7
-7y= -7
y=1

x-3y=4
x=4+3y
x=4+3×1=7