Answer:
the sum of any 2 sides must be greater than the 3rd side
7 is too short because 7+5 is not greater than 12
the length must be greater than 7
the length must be less than 17 because 5+12 is not greater than 17
let x=length of the third side
7<x<17 (in inches)
Step-by-step explanation:
sorry i am not right