Which one should I use
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Answer:
Pythagorean Theorem and Sine
Step-by-step explanation:
you could use pythagorean theorem to find the 3rd side, then use inverse sine of c.
Using the equation a2 + b2 = c2
Subtract 13squared from 5squared
169-25
then take the square root of the answer- which is 12
then do the inverse of sine
that should give you the missing angle