Solve for x
x = -\frac{7}{4} = -1\frac{3}{4} = -1.75
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7\left(x-2\right)+21=3x
Multiply both sides of the equation by 21, the least common multiple of 3,7.
7x-14+21=3x
Use the distributive property to multiply 7 by x-2.
7x+7=3x
Add -14 and 21 to get 7.
7x+7-3x=0
Subtract 3x from both sides.
4x+7=0
Combine 7x and -3x to get 4x.
4x=-7
Subtract 7 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-7}{4}
Divide both sides by 4.
x=-\frac{7}{4}
Fraction \frac{-7}{4} can be rewritten as -\frac{7}{4} by extracting the negative sign.
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{ x } ^ { 2 } - 4 x - 5 = 0
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4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
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699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}