Answer: 15
Step-by-step explanation:
For this question you have to use pythagoras' theorem.
Pythagoras' theorem is c²=a²+b²
So c is the hypotenuse and the hypotenuse is always opposite the right angle.
So the equation would be c²=9²+12²
Then 9²=81 and 12²=144
So the equation would then be c²=81+144
So c²=225
Then you just want to find c on it's own so you have to square root it which is 15.
