Question 494372: 3x+3y=-9
3x-3y=-21
Answer by Maths68(1474)   (Show Source):
You can put this solution on YOUR website! 3x+3y=-9 ...........(1)
3x-3y=-21...........(2)
Add (1) and (2)
3x+3y=-9
3x-3y=-21
------------
6x=-30
x=-30/6
x=-5
Put the value of x in either equations (1) or (2)
3x+3y=-9 ...........(1)
3(-5)+3y=-9
-15+3y=-9
3y=-9+15
3y=-9+15
3y=6
y=6/3
y=2
Solution Set (-5,2)
Check:
Put the value of x and y in either equations (1) or (2)
3x-3y=-21...........(2)
3(-5)-3(2)=-21
-15-6=-21
-21=-21
|
|
|
