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3 votes
Can anyone explain how to expand and simplify 3(2a+5) +5 (a-2)

2 Answers

3 votes
First of all you need to expand this expression. you do this by multiplying the number outside the brackets with each term inside the brackets. this is the first one ; 3 x 2a = 6a, 3 x 5 = 15. the extra + sign in the first brackets stays between the two terms, so the first set of brackets is now 6a + 15. now we have to look at the second ; 5 x a = 5a, 5 x 2 = 10, like the extra + sign, the extra - sign stays between the two terms as well, so the second bracket is now 5a-10. you put them together to get 6a + 15 + 5a - 10.

next you need to simplify the expression. first you need to group like terms, e.g. the numbers and the letters. 6a + 15 +5a -10. the 6a + 5a = 11a and the 15 - 10 = +5. you then put these two terms together to get your final answer of

11a + 5


User Desislav Kamenov
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2 votes
Take the first bracket and it's multiplication, 3(2a+5)
You expand my multiplying everything inside the bracket by the number outside.
3*2a = 6a
3*5 = 15
Then multiply out the second bracket, 5(a-2)
5*a = 5a
5*-2 = -10
So now you have 6a + 15 + 5a - 10
Simplify it by collecting like terms, and you have:
11a + 5
And that's the answer, hope I helped!
User Nghauran
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