Solve for a
a=7
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3a+9-\left(2a+7\right)=9
Use the distributive property to multiply 3 by a+3.
3a+9-2a-7=9
To find the opposite of 2a+7, find the opposite of each term.
a+9-7=9
Combine 3a and -2a to get a.
a+2=9
Subtract 7 from 9 to get 2.
a=9-2
Subtract 2 from both sides.
a=7
Subtract 2 from 9 to get 7.
Examples
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y = 3x + 4
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Matrix
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Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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