SOLUTION: 4x+5y=5 8x+10y=10 solve using the elimination method

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Question 378720: 4x+5y=5
8x+10y=10
solve using the elimination method
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

Start with the given system of equations:
system%284x%2B5y=5%2C8x%2B10y=10%29


-2%284x%2B5y%29=-2%285%29 Multiply the both sides of the first equation by -2.


-8x-10y=-10 Distribute and multiply.


So we have the new system of equations:
system%28-8x-10y=-10%2C8x%2B10y=10%29


Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:


%28-8x-10y%29%2B%288x%2B10y%29=%28-10%29%2B%2810%29


%28-8x%2B8x%29%2B%28-10y%2B10y%29=-10%2B10 Group like terms.


0x%2B0y=0 Combine like terms.


0=0Simplify.


Since 0=0 is ALWAYS true, this means that there are an infinite number of solutions.

So the system is consistent and dependent.


If you need more help, email me at jim_thompson5910@hotmail.com

Also, feel free to check out my tutoring website

Jim