Question

11a + 15b - 8c + 7d
10a + 9c - 13d
9a + 8b - 11c - 17d
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30a + 23b - 10c - 23d
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please explain this answer its of class 8 chapter algebraic expressions. i dont get how there was 10c in the answer and also 23b, 23d, 30a, also i dont get if we use those equations like (++)= + (+-) = - (- -) = +, sorry if its confusing

Answer 1

Step-by-step explanation:

(11a+15b-8c+7d)+(10a+9c-13d)+(9a+8b-11c-17d)

a(11+10+9)+b(15+8)+c(-8+9-11)+d(7-13-17)

a(30)+b(23)+c(-10)+d(-23)

30a+23b-10c-22d

hope you understand!

Answer 2

Hey friend, the right answer will be :-

$\: \: 11a + 15b \: - 8c \: + 7d \\ \ \: 10a \: + 0b \: + 9c \: - 13d \\ \: \: 9a \: + 8b \: - 11c \: - 17d \\ \: \: \: \: \: \: \: \: \: \: \: \: (add \: these) \\ \\ \: \: 30a \: + 23b \: - 10c \: - 23d$

I hope this will help you....