SOLUTION
A triangle has three sides. The sides of this triangle are 7 inches, 5inches and the unknown side.
Let the unknown side be x inches.
Perimeter is distance around a plane shape.
The perimeter of this triangle is 19,
![\begin{gathered} \text{ That is the perimeter 1}9=7+5+x \\ 19\text{ = 12 }+x \\ x\text{ = 19 - 12 } \\ x\text{ = 7 inches } \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/fpt0719ri1qgkvnfdg6qwa1nqcj5xjy9tl.png)
Therefore, the other side is 7 inches