Determine the value of x. Write the answer in an inequity. Use x only once in the

 1 < x < 25

Step-by-step explanation:

The sum of two sides must be GREATER than the third side.

      a +  b > c              a + c > b              b + c > a

     12 + 13 > x             12 + x > 13            13 + x > 12

          25  > x                     x > 1                      x > -1

           x < 25                     1 < x

Length cannot be negative so disregard x > -1

We are left with   1 < x  and   x < 25  

                                 1 < x < 25