Question

3. Simplify and find the value of the
expression 6x’y – 3(2x²y – 4y) when:

c) y = 6
​

Answer 1

Answer:

Add the following:

(i) 7abc, −5abc, 9abc, −8abc

(ii) 2x2y, − 4x2y, 6x2y, −5x2y

ANSWER:

Adding the given terms, we have

(i) 7abc + (- 5abc) + (9 abc) + (- 8abc)

= 7abc - 5abc + 9abc - 8abc

= (7 - 5 + 9 - 8)abc

= (16 - 13)abc

= 3abc

(ii) 2x2y + (- 4x2y) + 6x2y + (- 5x2y)

= 2x2y - 4x2y + 6x2y - 5x2y

= (2 - 4 + 6 - 5)x2y

= (8 - 9)x2y

= -x2y