Question

Serena is writing an expression that is equivalent to 12ab – 6b, but she has not completed it.

__?__ (2 a minus 1)

What is missing from the expression?
6b
6ab
6
ab

Answer 1

A

Explanation:

Answer 2

Given:

The expression is

`12ab-6b`

The equivalent expression of this expression is

`\_\_\_?\_\_\_(2a-1)`

To find:

The missing value.

Solution:

We have,

`12ab-6b`

The factor form of
`12ab` is

`12ab=2* 2* 3* a* b`

The factor form 6b is

`6b=2* 3* b`

The common factors of
`12ab` and
`6b` are
`2,3,b`.

`HCF(12ab,6b)=2* 3* b`

`HCF(12ab,6b)=6b`

Taking out the highest common factors(HCF) from the given expression, we get

`12ab-6b=6b(2a-1)`

On comparing this with
`\_\_\_?\_\_\_(2a-1)`, we get the missing value which is equal to
`6b`.

Therefore, the correct option is A.