Question

solve systems by substitution method x + y = 12 3x - y = 20

Answer 1

Step-by-step explanation:

x+y=12

3×+y=20

×=12-y

3 (12-y)+y=20

36-3y+y=20

36-4y=20

-4y=20-36

-4y= -16

y =16÷4

y=4

×+y=12

×+4=12

×=12-4

×=8

therefoer;y=4,x=8