Solve for x
x=\frac{3}{8}=0.375
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x+3-21x+12x=0
Multiply 7 and 3 to get 21.
-20x+3+12x=0
Combine x and -21x to get -20x.
-8x+3=0
Combine -20x and 12x to get -8x.
-8x=-3
Subtract 3 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-3}{-8}
Divide both sides by -8.
x=\frac{3}{8}
Fraction \frac{-3}{-8} can be simplified to \frac{3}{8} by removing the negative sign from both the numerator and the denominator.
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y = 3x + 4
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Matrix
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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