Answer:
Option c
or
![y \leq 21](https://img.qammunity.org/2020/formulas/mathematics/middle-school/7katm6kjchi1idso0a41ixbjizyglxrbxt.png)
Explanation:
The absolute value is a function that transforms any value x into a positive number.
Therefore, for the function
x> 0 for all real numbers.
Then the inequation:
has two cases
if
(i)
if
(ii)
We solve the case (i)
![y \leq 9 + 12\\y\leq21](https://img.qammunity.org/2020/formulas/mathematics/middle-school/rggda4heizia771w4k72lkk6nov5szdzyh.png)
We solve the case (ii)
![-y +9 \leq 12\\-y \leq 12-9\\y \geq -3](https://img.qammunity.org/2020/formulas/mathematics/middle-school/fanwwsbwlc9qujb42t9pj9gfhs97c2hh7n.png)
Then the solution is:
or
![y \leq 21](https://img.qammunity.org/2020/formulas/mathematics/middle-school/7katm6kjchi1idso0a41ixbjizyglxrbxt.png)