Question

Find the difference. –12 – (–21) = _____

Answer 1

the answer of this expression is 9.

Explanation:

we have given expression

- 12 -( - 21)

we have to find the difference

according to the addition and subtraction rule:

( - ) . ( - ) = (+)

this means

a -( - b ) = a + b

we use above rule to find the difference of - 12 - ( - 21 ).

- 12 - ( - 21 ) = - 12 + 21

- 12 + 21 = 9

9 is the required answer .

Answer 2

The value of given expression is 9.

Explanation:

The given expression is

`12-(-21)`

According to the rule of addition and subtraction,

`(-)\cdot (-)=(+)`

It means,

`a-(-b)=a+b`

By using above rule we get,

`12-(-21)=-12+21`

`12-(-21)=9`

Therefore the value of given expression is 9.