Whats the area of a 7in by 5in triangle

You haven't given us enough information to find the area of the triangle.

All we know about the triangle is the length of two of its sides.

The third side can be any length between 2in and 12 in.

Every possible length for the third side gives the triangle

a different area.

If the measurements are the base and the height : Area=17,5 in ^2

7/2=3,5

3,5x5=17,5