SOLUTION: solving by substitution. x+y=4 x=y+1

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Question 442456: solving by substitution. x+y=4
x=y+1
Answer by swincher4391(1107) About Me  (Show Source):
You can put this solution on YOUR website!
They have already solved the 2nd one for x. So let's use that.
Since we know x=y+1, then we can substitute that for where we see x in the 1st.
x+y=4
(y+1) + y =4
2y + 1 = 4
2y = 3
y = 3/2
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Now we need to plug in 3/2 back into one of our original equations.
Let's use the 2nd.
x = (3/2) + 1
x = 3/2 + 2/2
x = 5/2
So our solution is (5/2, 3/2) or x=5%2F2y=3%2F2