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Question:

Help With Math, Expanding brackets?

can you show me how to work out 2a+(a-2b)and2a-(a-2b)the fact that there's a sign AFTER the first number throws me off. thanks in advance!

Answer:

the sign means you multiply the sign on the inside and the outside, a positive times a negetive a negative, a negetive times a negative a positive, a positive times a positive a positive. 2a +(a-2b) 2a(squared) - 4ab
If these are written correctly, then the bracket actually has no effect in this case - it is simply a matter of applying the addition and subtraction signs. The expressions reduce to: 3a-2b and a-2b
In both those cases the brackets don't change anything. In other words you can write them withoput brackets and they will mean the same thing 2a+(a-2b) 2a + a - 2b 3a - 2b 2a-(a-2b) 2a -a -2b a - 2b If you get stuck on stuff like that try replacing a and b with real numbers to check your answer eg in the first one if a 2 and b 5 Then 2a+(a-2b) 4+(2-10) 4 + 2 - 10 -4 Does 3a - 2b -4? --6 - 10 -4 so yes

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