SOLUTION: i couldnt figure out how to work this problem. im in 9th grade in algebra 1. what is y=4x-8 y=2x+10

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Question 176227: i couldnt figure out how to work this problem. im in 9th grade in algebra 1. what is

y=4x-8
y=2x+10
Found 3 solutions by Alan3354, nerdybill, jim_thompson5910:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
i couldnt figure out how to work this problem. im in 9th grade in algebra 1. what is
y=4x-8
y=2x+10
------------
It's not the usual method, but since they both equal y:
4x-8 = 2x+10
2x = 18
x = 9
---------
y = 4*9-8
y = 28
We're done.

Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
y=4x-8 (equation 1)
y=2x+10 (equation 2)
.
Plug in the value of 'y' from equation 1 into equation 2 and solve for 'x':
y=2x+10
4x-8=2x+10
2x-8 = 10
2x = 18
x = 9 (solution for x)
.
Plug the above into equation 1 and solve for 'y':
y=4x-8
y=4(9)-8
y=36-8
y=28 (solution for y)

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
y=4x-8 Start with the first equation.


2x%2B10=4x-8 Plug in y=2x%2B10 (which is the second equation). In other words, replace each "y" with 2x%2B10 to eliminate the y variable.


2x=4x-8-10 Subtract 10 from both sides.


2x-4x=-8-10 Subtract 4x from both sides.


-2x=-8-10 Combine like terms on the left side.


-2x=-18 Combine like terms on the right side.


x=%28-18%29%2F%28-2%29 Divide both sides by -2 to isolate x.


x=9 Reduce.

-----------------------------------

y=4x-8 Go back to the first equation.


y=4%289%29-8 Plug in x=9


y=36-8 Multiply


y=28 Subtract


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Answer:


So the solutions are x=9 and y=28 which form the ordered pair (9,28)


So the system is consistent and independent.