SOLUTION: Please help to solve the use of method of substitution to solve the system of linear equations. 4x-y=3 and 9x-2y=11
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Question 789054: Please help to solve the use of method of substitution to solve the system of linear equations. 4x-y=3 and 9x-2y=11 Found 2 solutions by stanbon, rothauserc:Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! 4x-y=3
9x-2y=11
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Modify for elimination:
8x - 2y = 6
9x - 2y = 11
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Subtract and solve for "x":
x = 5
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Solve for "y":
4x - y = 3
20 - y = 3
y = 17
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Cheers,
Stan H.
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You can put this solution on YOUR website! we are given two equations in two unknowns
4x-y = 3
9x-2y = 11
solve first equation for y
-y = 3 -4x
y = 4x -3
substitute for y in second equation
9x -2*(4x -3) = 11
9x -8x +6 = 11
x = 5
now substitute for x in fist equation
4*5 -y = 3
20 -y = 3
y = 17
now subtitute for x and y in second equation as a check
9*5 - 2*17 = 11
45 - 34 = 11
11 = 11
so x = 5 and y = 17 answers check
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