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

Question 865384: I need to solve for both x and y
x+y=20 x=y-4
Answer by jim_thompson5910(35256) (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

=======================================================

Final Answer: x = 8, y = 12

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

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