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2a-7b
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2a-7b
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-a-\left(-2b\right)+3\left(a-3b\right)
To find the opposite of a-2b, find the opposite of each term.
-a+2b+3\left(a-3b\right)
The opposite of -2b is 2b.
-a+2b+3a-9b
Use the distributive property to multiply 3 by a-3b.
2a+2b-9b
Combine -a and 3a to get 2a.
2a-7b
Combine 2b and -9b to get -7b.
-a-\left(-2b\right)+3\left(a-3b\right)
To find the opposite of a-2b, find the opposite of each term.
-a+2b+3\left(a-3b\right)
The opposite of -2b is 2b.
-a+2b+3a-9b
Use the distributive property to multiply 3 by a-3b.
2a+2b-9b
Combine -a and 3a to get 2a.
2a-7b
Combine 2b and -9b to get -7b.
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