SOLUTION: I don't understand the systems 8x+4y=6 4x=3-y I got the answers x=6/8 and y=0 im not sure if I did it correctly.

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Question 639187: I don't understand the systems
8x+4y=6
4x=3-y
I got the answers x=6/8 and y=0 im not sure if I did it correctly.
Found 2 solutions by solver91311, MathLover1:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


If you substitute your and values into each of the equations, do you get a true statement BOTH times? If so, you have done the problem correctly. If not, you have an error. Let me know what you find out.

John

My calculator said it, I believe it, that settles it
The Out Campaign: Scarlet Letter of Atheism

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
8x%2B4y=6...this is a standard form
4x=3-y....->..a standard form is 4x%2By=3
you got the answers x=6%2F8 and y=0 which is correct..you can reduce x=6%2F8 to3%2F4 if you divide both numerator and denominator by 2
Solved by pluggable solver: Solve the System of Equations by Graphing



Start with the given system of equations:


8x%2B4y=6

4x%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


8x%2B4y=6 Start with the given equation



4y=6-8x Subtract 8+x from both sides



4y=-8x%2B6 Rearrange the equation



y=%28-8x%2B6%29%2F%284%29 Divide both sides by 4



y=%28-8%2F4%29x%2B%286%29%2F%284%29 Break up the fraction



y=-2x%2B3%2F2 Reduce



Now lets graph y=-2x%2B3%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+-2x%2B3%2F2%29+ Graph of y=-2x%2B3%2F2




So let's solve for y on the second equation


4x%2By=3 Start with the given equation



1y=3-4x Subtract 4+x from both sides



1y=-4x%2B3 Rearrange the equation



y=%28-4x%2B3%29%2F%281%29 Divide both sides by 1



y=%28-4%2F1%29x%2B%283%29%2F%281%29 Break up the fraction



y=-4x%2B3 Reduce





Now lets add the graph of y=-4x%2B3 to our first plot to get:


+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+-2x%2B3%2F2%2C-4x%2B3%29+ Graph of y=-2x%2B3%2F2(red) and y=-4x%2B3(green)


From the graph, we can see that the two lines intersect at the point (3%2F4,0) (note: you might have to adjust the window to see the intersection)