SOLUTION: I need to solve for both x and y x+y=20 x=y-4

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Question 865384: I need to solve for both x and y
x+y=20 x=y-4

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
x+y=20 ... Start with the first equation.


y-4+y=20 ... Replace x with y-4 (since x = y-4 is the second equation).


Now we solve for y


y-4+y=20


2y-4=20


2y=20+4


2y=24


y=24/2


y = 12


Once we know that y = 12, we plug this into any equation that has x,y in it to solve for x. The easiest to pick on is the one where x is already isolated.


x = y-4


x = 12-4 ... replace y with 12 (since we just found that y = 12)


x = 8


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Final Answer: x = 8, y = 12


The answer as an ordered pair is (8,12). Visually, this is where the two lines intersect.