SOLUTION: x + 2y = 5 x + y = 3

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Question 944761: x + 2y = 5
x + y = 3

Found 2 solutions by MathLover1, macston:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

x+%2B+2y+=+5
x+%2B+y+=+3
-----------------
Solved by pluggable solver: Solve the System of Equations by Graphing



Start with the given system of equations:


1x%2B2y=5

1x%2By=3





In order to graph these equations, we need to solve for y for each equation.




So let's solve for y on the first equation


1x%2B2y=5 Start with the given equation



2y=5-x Subtract +x from both sides



2y=-x%2B5 Rearrange the equation



y=%28-x%2B5%29%2F%282%29 Divide both sides by 2



y=%28-1%2F2%29x%2B%285%29%2F%282%29 Break up the fraction



y=%28-1%2F2%29x%2B5%2F2 Reduce



Now lets graph y=%28-1%2F2%29x%2B5%2F2 (note: if you need help with graphing, check out this solver)



+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+%28-1%2F2%29x%2B5%2F2%29+ Graph of y=%28-1%2F2%29x%2B5%2F2




So let's solve for y on the second equation


1x%2By=3 Start with the given equation



1y=3-x Subtract +x from both sides



1y=-x%2B3 Rearrange the equation



y=%28-x%2B3%29%2F%281%29 Divide both sides by 1



y=%28-1%2F1%29x%2B%283%29%2F%281%29 Break up the fraction



y=-x%2B3 Reduce





Now lets add the graph of y=-x%2B3 to our first plot to get:


+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+%28-1%2F2%29x%2B5%2F2%2C-x%2B3%29+ Graph of y=%28-1%2F2%29x%2B5%2F2(red) and y=-x%2B3(green)


From the graph, we can see that the two lines intersect at the point (1,2) (note: you might have to adjust the window to see the intersection)

Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
x + 2y = 5
x + y = 3
Solved by pluggable solver: Linear System solver (using determinant)
Solve:
+system%28+%0D%0A++++1%5Cx+%2B+2%5Cy+=+5%2C%0D%0A++++1%5Cx+%2B+1%5Cy+=+3+%29%0D%0A++

Any system of equations:


has solution

or



(x=1, y=2}

ANSWER x=1, y=2
CHECK
x+2y=5
1+2(2)=5
5=5
x+y=3
1+2=3
3=3