You can put this solution on YOUR website! Multiply the second equation by -2
-2(2a+2b=6)
-4a - 4b = -12
...
Add to the first equation
3a + -4a + 4b - 4b = 9 + -12
Combine like terms
-a = -3
Divide both sides by -1
a = 3
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Plug the a value into either equation
3(3) + 4b = 9
9 + 4b = 9
Isolate the b variable
4b = 0
Divide both sides by 4
b = 0
...
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a = 3
b = 0
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