SOLUTION: solve the following simultaneous equations by the substitution technique 4x + y = 9 3x +2y = 13

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Question 955459: solve the following simultaneous equations by the substitution technique
4x + y = 9
3x +2y = 13

Found 2 solutions by stanbon, macston:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
4x + y = 9
3x +2y = 13
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Modify for elimination::
8x + 2y = 18
3x + 2y = 13
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Subtract::
5x = 5
x = 1
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Solve for "y"::
4x + y = 9
4 + y = 9
y = 5
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Cheers,
Stan H.
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Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
4x+y=9
y=9-4x
3x+2y=13 Substitute for y
3x+2(9-4x)=13
3x+18-8x=13 Subtract 18 from each side.
-5x=-5 Divide each side by -5
x=1 ANSWER 1: x=1
4x+y=9 Use value for x
4(1)+y=9 Subtract 4 from each side.
y=5 ANSWER 2: y=5
CHECK:
3x+2y=13
3(1)+2(5)=13
3+10=13
13=13