Question

if A=7b-3c + 10d,B=4b-c+8d and C=2a+b+c,find:
1.A+B
2.A+B+C
3.B-C
4.2A-C​

Answer 1

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Answer 2

Given,

$\rm{A=7b-3c + 10d} \\ \rm{B=4b-c+8d} \\ \rm{C=2a+b+c}$

Now,

$\huge = > \bf{A+B} \\ \\ \tt= > 7b - 3c + 10d + 4b - c + 8d \\ \tt = > 11b - 4c + 18d$

And,

$\huge = > \bf{A+B+C} \\ \\ \tt = > 7b-3c + 10d + 4b \cancel{-c}+8d + 2a+b\cancel{ + c} \\ \tt = > 2a + 12b - 3c + 18d$

And,

$\huge = > \bf{B-C} \\ \\ \tt= >4b-c+8d - (2a+b+c) \\ \tt = > 4b - c + 8d - 2a - b - c \\ \tt = > 3b - 2c - 2a$

And,

$\huge \bf = > 2A-C \\ \\ \tt = >2(7b-3c + 10d) - (2a+b+c ) \\ \tt = > 14b - 6c + 20d - 2a - b - c \\ \tt = > 13b - 7c - 2a + 20d$