Question

What is the simplified expression for –3cd – d(2c – 4) – 4d?
–5cd
cd – 8d
5cd – 8d
–5cd – 8d

Answer 1

be careful with the signs when you distribute -d over (2c - 4)

Answer 2

thank you but I still need help

Answer 3

-d(2c - 4) = -d*2c -d*-4 = -2cd + 4d

(note -d * -4 = + 4d)

Answer 4

so you get
-3cd - 2cd +4d - 4d

can you continue?

Answer 5

yeah I got that

Answer 6

great

Answer 7

now I am lost

Answer 8

well its important to rememger that you can only add/subtract LIKE terms

eg x and 3x are like terms

so are 2y and - 3y

here we have -3cd and -2cd
and -4d and + 4d


what does -3cd - 2cd simplify to?

Answer 9

can you work out - 3 - 2 ?

Answer 10

-5

Answer 11

right so -3cd - 2cd = -5cd

Answer 12

and what does -4 + 4 come to?

Answer 13

0