SOLUTION: Solve the system, if possible. (If the system is inconsistent, enter INCONSISTENT. If the system is dependent, enter DEPENDENT.) 4a − 3b = 1 6a − 8c = 1 2b − 4

Algebra ->  Expressions-with-variables -> SOLUTION: Solve the system, if possible. (If the system is inconsistent, enter INCONSISTENT. If the system is dependent, enter DEPENDENT.) 4a − 3b = 1 6a − 8c = 1 2b − 4      Log On


   



Question 977313: Solve the system, if possible. (If the system is inconsistent, enter INCONSISTENT. If the system is dependent, enter DEPENDENT.)
4a − 3b = 1
6a − 8c = 1
2b − 4c = 0

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the system, if possible. (If the system is inconsistent, enter INCONSISTENT. If the system is dependent, enter DEPENDENT.)
4a − 3b = 1
6a − 8c = 1
2b − 4c = 0
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What's the problem with the minus signs?
4a - 3b = 1
6a - 8c = 1
2b - 4c = 0 --> b - 2c = 0 --> b = 2c
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Sub for b in the 1st equation.
4a - 3b = 1 --> 4a - 3(2c) = 1 --> 4a - 6c = 1
6a - 8c = 1
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4a - 6c = 1 Eqn A
6a - 8c = 1 Eqn B
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12a - 18c = 3 Eqn A times 3
12a - 16c = 2 Eqn B times 2
-------------------------------------- Subtract
-2c = 1
c = -1/2 ****************************************************
------
4a - 6c = 1
4a + 3 = 1
a = -1/2 ****************************************************
--------
4a - 3b = 1
-2 - 3b = 1
b = -1 *******************************************************