Question

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

Answer 1

Answer:

The value of given expression is 9.

Step-by-step 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.

Answer 2

Answer:

the answer of this expression is  9.

Step-by-step 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 .