I'm going to assume you've learn sin, cos, and tan. To find a you must do:
[tex] sin^{ - 1} = \frac{a}{12}[/tex]
Once you find a, you can use the Pythagorean Theorem to find b:
[tex] {a}^{2} + {b}^{2} = {c}^{2} [/tex]
Or you can do:
[tex]cos^{ - 1} = \frac{b}{12} [/tex]
You can find these functions on a scientific calculator. Let me now if you need more help.
