Solve for a
a=9
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a+4a-20=2a+7
Use the distributive property to multiply 4 by a-5.
5a-20=2a+7
Combine a and 4a to get 5a.
5a-20-2a=7
Subtract 2a from both sides.
3a-20=7
Combine 5a and -2a to get 3a.
3a=7+20
Add 20 to both sides.
3a=27
Add 7 and 20 to get 27.
a=\frac{27}{3}
Divide both sides by 3.
a=9
Divide 27 by 3 to get 9.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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y = 3x + 4
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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
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Limits
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