SOLUTION: substitute, x=2y+8 7x+y=101

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Question 179020: substitute,
x=2y+8
7x+y=101
Found 2 solutions by vleith, checkley75:
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
Given x=2y%2B8 and 7x%2By=101
Use the value of x in the first equation and substitute it into the second equation
7x%2By=101
7%282y%2B8%29%2By=101
14y+%2B+56+%2B+y+=+101
15y+%2B+56+=+101
15y+=+101+-+56
15y+=+45
y+=+45%2F15
y+=+3
Now take that value for y and substitute it into the first equation to solve for x
x=+2y+%2B+8
x+=+2%283%29+%2B+8
x+=+6+%2B+8
x+=+14
Check your answer using equation 2
Does 7%2814%29+%2B+3+=+101???
98+%2B+3+=+101+?
yes it does
so x = 14 and y = 3

Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
x=2y+8
7x+y=101
7(2y+8)+y=101
14y+56+y=101
15y=101-56
15y=45
y=45/15
y=3 ans.
x=2*3+8
x=6+8
x=14 ans.
Proof:
7*14+3=101
98+3=101
101=101