Solve for a
a = \frac{3}{2} = 1\frac{1}{2} = 1.5
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28a-21-\left(2a+1\right)\times 9=2\left(a-9\right)
Use the distributive property to multiply 7 by 4a-3.
28a-21-\left(18a+9\right)=2\left(a-9\right)
Use the distributive property to multiply 2a+1 by 9.
28a-21-18a-9=2\left(a-9\right)
To find the opposite of 18a+9, find the opposite of each term.
10a-21-9=2\left(a-9\right)
Combine 28a and -18a to get 10a.
10a-30=2\left(a-9\right)
Subtract 9 from -21 to get -30.
10a-30=2a-18
Use the distributive property to multiply 2 by a-9.
10a-30-2a=-18
Subtract 2a from both sides.
8a-30=-18
Combine 10a and -2a to get 8a.
8a=-18+30
Add 30 to both sides.
8a=12
Add -18 and 30 to get 12.
a=\frac{12}{8}
Divide both sides by 8.
a=\frac{3}{2}
Reduce the fraction \frac{12}{8} to lowest terms by extracting and canceling out 4.
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
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Limits
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