SOLUTION: Solve by elimination by substitution. X-y=4 { 4y-x=14

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Question 453115: Solve by elimination by substitution.
X-y=4
{
4y-x=14

Answer by pedjajov(51) About Me  (Show Source):
You can put this solution on YOUR website!
We have system of two linear equations with two variables:
:
x-y=4
4y-x=14
:
Solve first for x:
x=4+y
:
Now substitute this in second:
4y-(4+y)=14, get rid of parentheses:
4y-4-y=14, add 4 to both sides of equation
4y-4-y+4=14+4, regroup
4y-y+4-4=18, combine like terms and numbers
3y=18, divide by 3
y=6
:
Now go back and use this value for y in expression we got for x:
x=4+y
x=4+6
x=10
:
Solution is x=10 and y=6