Answer:
a. 12 mm
The Pythagorean Theorem states that a^2 + b^2 = c^2 with a and b being lengths of legs and c being the length of a hypotenuse. So we can use our givens to solve for the remaining leg.
9^2 + b^2 = 15^2
81 + b^2 = 225
b^2 = 144
b = 12
Step-by-step explanation:
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