5x + y = 15
y = -5x + 15
Substituting y= -5x+15 from first equation into second equation:
3x + 2y = 16
3x + 2·(-5x + 15) = 16
3x - 10x + 30 = 16
-7x + 30 = 16
7x = 30 - 16 = 14
x = 2
Substituting x=2 into the first equation:
5x + y = 15
5(2) + y = 15
10 + y = 15
y = 15 - 10
y = 5
So your final answers are x=2 and y=5.
3x + 2y + y - 3x = 180
3y = 180
y = 180/3
y = 60
3x = y - 3x
Let y = 60
3x = 60 - 3x
3x + 3x = 60
6x = 60
x = 60/6
x = 10
Answer: x = 10, y = 60
The answer is 1188.
Hope it helped :)