Answer:
The length of b is <u>12 mm</u>.
Step-by-step explanation:
<u>Solution</u> :
Here, we have given that the two sides of triangle are 9 mm and 15 mm.
Finding the third side of triangle by pythagoras theorem formula :

Substituting all the given values in the formula to find the third side of triangle :










Hence, the length of b is 12 mm.
