SOLUTION: Substitition- x + y = 13 y - x = -7

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Question 121692This question is from textbook
: Substitition-
x + y = 13
y - x = -7This question is from textbook

Found 2 solutions by Nellene Mae, Fombitz:
Answer by Nellene Mae(3) About Me  (Show Source):
You can put this solution on YOUR website!
im not sure of my answer coz you just have to substitute d negative 7...

Answer by Fombitz(13823) About Me  (Show Source):
You can put this solution on YOUR website!
1.x+%2B+y+=+13
2.y+-+x+=+-7
Use equation 2 to get an expression for y in terms of x.
2.y+-+x+=+-7
y+=+-7+%2B+x
Now substitute that expression into equation 1 and solve for x.
1.x+%2B+y+=+13
x+%2B+%28-7%2Bx%29+=+13
2x-7=13
2x=20
highlight%28x=10%29
From equation 2,
y+=+-7+%2B+x
y+=+-7+%2B+10
highlight%28y+=+3%29
Check your answers.
1.x+%2B+y+=+13
10%2B3=13
13=13
True statement
2.y+-+x+=+-7
3-10=-7
-7=-7
Ture statement.
Your answers led to true statements.
They are good answers.