SOLUTION: Hey! Allright- Well my problem isto solve by using the Substitution method! I am having a small difficulty with it. the problem is *y=5x 2x+y=28* What I got

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Question 129933This question is from textbook algebra
: Hey! Allright- Well my problem isto solve by using the Substitution method! I am having a small difficulty with it.
the problem is *y=5x
2x+y=28*
What I got was (4,20) The problem I am having is cheaking to see if it is the right answer.
Please help me with my problem?
Please and Thank You=) This question is from textbook algebra

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Start with the given system
2x%2By=28
y=5x



2x%2B5x=28 Plug in y=5x into the first equation. In other words, replace each y with 5x. Notice we've eliminated the y variables. So we now have a simple equation with one unknown.


2x%2B5x=28 Distribute


7x=28 Combine like terms on the left side


x=%2828%29%2F%287%29 Divide both sides by 7 to isolate x



x=4 Divide




Now that we know that x=4, we can plug this into y=5x to find y



y=5%284%29 Substitute 4 for each x


y=20 Simplify


So our answer is x=4 and y=20 which also looks like



Notice if we graph the two equations, we can see that their intersection is at . So this verifies our answer.


Graph of 2x%2By=28 (red) and y=5x (green)