SOLUTION: how to solve by substitution 4x+y=11;2x+5y=1

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Question 499454: how to solve by substitution 4x+y=11;2x+5y=1
Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
4x+y=11
2x+5y = 1
.
4x+y = 11
subtract 4x from both sides
y = -4x +11
.
substitute that into the 2nd equation
.
2x + 5(-4x + 11) = 1
.
multiply through
2x -20x +55 = 1
.
collect terms & subtract 55 from both sides
-18x = -54
.
divide both sides by -18
x = -54/-18
x = 54/18
x = 3
.
Now substitute that value to find 'y'
.
4x+y=11
4(3) + y = 11
12 + y = 11
y = -1
.
x = 3
y = -1
.
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