SOLUTION: x=y-5 3x+y=1

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Question 1205685: x=y-5
3x+y=1
Found 3 solutions by josgarithmetic, greenestamps, MathTherapy:
Answer by josgarithmetic(39617) About Me  (Show Source):
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


One of the two given equations tells you what x is in terms of y. When that is the case, substitution is the obvious logical straightforward approach... although many other methods will get you to the answer.

x=y-5

So...

3x%2By=3%28y-5%29%2By=3y-15=y=4y-15=1
4y-15=1
4y=16
y=4

Then

x=y-5=4-5=-1

ANSWER: (x,y)=(-1,4)

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!
x=y-5

3x+y=1

x = y - 5___x - y = - 5 ----- eq (i)
           3x + y = 1 ------- eq (ii)
               4x = - 4 ----- Adding eqs (i) & (ii)
              

Proceed by substituting - 1 for x into any of the 2 equations to get the value of y.