Answer:
9 units
Step-by-step explanation:
Using Pythagoras' identity on the right triangle.
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides.
Let x be the length of the other leg, then
x² + 12² = 15², that is
x² + 144 = 225 ( subtract 144 from both sides )
x² = 81 ( take the square root of both sides )
x = [tex]\sqrt{81}[/tex] = 9
