Solve for x
x=3
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3x-12+4x=9
Add 4x to both sides.
7x-12=9
Combine 3x and 4x to get 7x.
7x=9+12
Add 12 to both sides.
7x=21
Add 9 and 12 to get 21.
x=\frac{21}{7}
Divide both sides by 7.
x=3
Divide 21 by 7 to get 3.
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y = 3x + 4
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Matrix
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Simultaneous equation
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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Limits
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