SOLUTION: Solve using substitution method. a - 2b = 3 3a = 6b + 9

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Question 309347: Solve using substitution method.
a - 2b = 3
3a = 6b + 9

Found 2 solutions by ichudov, stanbon:
Answer by ichudov(507) About Me  (Show Source):
You can put this solution on YOUR website!

you just need to use the substitution solver
Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++1%5Ca+%2B+-2%5Cb+=+3%2C%0D%0A++++3%5Ca+%2B+-6%5Cb+=+9+%29%0D%0A++We'll use substitution. After moving -2*b to the right, we get:
1%2Aa+=+3+-+-2%2Ab, or a+=+3%2F1+-+-2%2Ab%2F1. Substitute that
into another equation:
3%2A%283%2F1+-+-2%2Ab%2F1%29+%2B+-6%5Cb+=+9 and simplify: So, we know that b=0=0. Since a+=+3%2F1+-+-2%2Ab%2F1, a=3.

Answer: system%28+a=3%2C+b=0=0+%29.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve using substitution method.
a - 2b = 3
3a = 6b + 9
-----------------
Rearrange:
a = 2b+3
----
Substitute for "a" and solve for "b":
2b+3 = 6b+9
4b = -6
b = -3/2
-----
Since a = 2b+3, a = 2(-3/2)+3 = 0
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Cheers,
Stan H.