SOLUTION: Hello, Can you show me how to solve the following using elimination method or the substitution method? 1. 8x+5y= 180.50 2. 12x+6y= 261.00

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: Hello, Can you show me how to solve the following using elimination method or the substitution method? 1. 8x+5y= 180.50 2. 12x+6y= 261.00       Log On


   



Question 1141834: Hello,
Can you show me how to solve the following using elimination method or the substitution method?
1. 8x+5y= 180.50
2. 12x+6y= 261.00

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
1) +8x+%2B+5y+=+180.5+
2) +12x+%2B+6y+=+261+
-----------------------------
Divide both sides of 2) by +3+
2) +4x+%2B+2y+=+87+
----------------------------
Multiply both sides of 1) by +2+
Multiply both sides of 2) by +5+
1) +16x+%2B+10y+=+361+
2) +20x+%2B+10y+=+435+
Subtract 1) from 20
2) +20x+%2B+10y+=+435+
1) +-16x+-+10y+=+-361+
-----------------------------
+4x+=+74+
+x+=+18.5+
--------------------
Plug this result back into 1) or 2)
2) +4%2A18.5+%2B+2y+=+87+
2) +74+%2B+2y+=+87+
2) +2y+=+13+
2) +y+=+6.5+
------------------------
check:
1) +8%2A18.5+%2B+5%2A6.5+=+180.5+
1) +148+%2B+32.5+=+180.5+
1) +180.5+=+180.5+
OK
2) +12%2A18.5+%2B+6%2A6.5+=+261+
2) +222+%2B+39+=+261+
2) +261+=+261+
OK