SOLUTION: how do you slove ts question usingthe sub method 6x+14y=54 3x+5y=30

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Question 716459: how do you slove ts question usingthe sub method
6x+14y=54
3x+5y=30
Found 2 solutions by stanbon, josmiceli:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
6x+14y=54
3x+5y=30
----
Solve the bottom equation for "y":
y = (30-3x)/5
--------------------
Substitute for "y" in the top equation and solve for "x":
6x + 14[(6-(3/5)x)] = 54
-------
6x + 84 - (42/5)x = 54
6x - (42/5)x = -30
(30/5)x - (42/5)x = -30
(-12/5)x = -30
-------
-12x = -150
x = 12.5
=================
Cheers,
Stan H.
=================

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Subtraction method?
Multiply both sides of (2) by +2+
and subtract (2) from (1)
+6x+%2B14y+=54%0D%0A%7B%7B%7B+-6x+-+10y+=-60+
+4y+=+-6+
+y+=+-3%2F2+
Substitute this result back into (1) or (2)
+3x%2B5y=30+
+3x%2B5%2A%28-3%2F2%29+=+30+
+3x+=+30+%2B+15%2F2+
+3x+=+75%2F2+
+x+=+25%2F2+
------------
check the answers:
+6x%2B14y+=+54+
+3x+%2B+7y+=+27+
+3%2A%2825%2F2%29+%2B+7%2A%28-3%2F2%29+=+27+
+75+-+21+=+54+
+54+=+54+
OK
You can check the other equation