SOLUTION: x+y=9 y=2x

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Question 570138: x+y=9
y=2x
Found 2 solutions by Maths68, sahnikdgp:
Answer by Maths68(1474) About Me  (Show Source):
You can put this solution on YOUR website!
x+y=9.........(1)
y=2x........(2)
Put value of y from (2) to (1)
x+y=9
x+2x=9
3x=9
3x/3=9/3
x=3...............(3)
Put the value of x in (2)
y=2x
y=2(3)
y=6
x,y=3,6


Check
Put the value of x and y in (1)
x+y=9.........(1)
3+6=9
9=9
Put the value of x and y in (2)
y=2x
6=2(3)
6=6

Answer by sahnikdgp(1) About Me  (Show Source):
You can put this solution on YOUR website!
x+y=9......1
y=2x.......2
or,y-2x=0...2
x+y=9......1
-2x+y=0.....2
or,3x=9
or, x=3
substituting x in equation (1),
x+y=9
or,3+y=9
or,y=9-3=6
answers-:x=3
y=6