Two sides of a triangle are given as 28 inches and 42 inches. find all possible lengths for the third side of the triangle

The longest side of  a triangle must be less than the sum of the other 2 sides

2 senarios

the 3rd side is the longest
the 3rd side is not the longest

for the 3rd side is the longest

3rdside<28+42
3rdside<70

for 3rd side isn't the longest
42 is longest
42<28+3rdside
14<3rdside

so we've got
3rdside<70 and 14<3rdside

so
14<3rdside<70

the 3rd side can be any number from 14in to 70in except 14in and 70in