SOLUTION: 1/2 x + 1/3 y = -3/10 1/2 x +4 y = 45/2 Solve by substitution

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Question 982406: 1/2 x + 1/3 y = -3/10
1/2 x +4 y = 45/2
Solve by substitution
Found 2 solutions by Edwin McCravy, stanbon:
Answer by Edwin McCravy(20063) About Me  (Show Source):
You can put this solution on YOUR website!
Notice I've changed the fractions, but yours is done 
EXACTLY like this one.  So use this as a model to do
yours by.



First let's clear of fractions
Multiply the first equation by LCD=30
and the second equation through by 3



system%2810x+%2B+15y+=+-36%2C%0D%0Ax+%2B+15y+=+37%29

Solve the second equation for x

x=37-15y

Substitute %2837-15y%29 for x in the first equation:

10x+%2B+15y+=+-36
10%2837-15y%29+%2B+15y+=+-36
370-150y%2B15y=-36
370-135y=-36
-135y=-406
y=%28-406%29%2F%28-135%29
y=406%2F135

Substitute in x=37-15y

x=37-15%28406%2F135%29
x=37-cross%2815%29%28406%2F%28cross%28135%5B9%5D%29%29%29

x=37-406%2F9%29

x=37%2A9%2F9-406%2F9

x=333%2F9-406%2F9

x=-73%2F9

Now do yours exactly the same way using the above as a model.

Edwin

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
1/2 x + 1/3 y = -3/10
1/2 x +4 y = 45/2
Solve by substitution
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1st:: Get rid of the denominators::
15x + 10y = -9
x + 8y = 45
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Solve for "x"::
x = 45-8y
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Substitute for "x" and solve for "y"::
15(45-8y) + 10y = -9
----
15*45-110y = -9
y = (15*45+9)/110
y = 342/55
====
Solve for "x":
x = 45-8[342/55]
x = -261/55
--------------
Check the answers
15x + 10y = -9
15(-261/55)+10(342/55) = -9
-9 = -9
-------
Cheers,
Stan H.
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