Question

3x+y=0, x-y=5 substitution method

Answer 1

Answer:

3x+y=0,

x-y=5

x=y+5

3x+y=0,

3(y+5)+y=0

3y+15+y=0

4y+15=0

4y=-15

y=-15/4

3x+y=0,

3x-15/4=0

(12x-15)/4=0

12x-15=0

12x=15

x=15/12

x=4/3