4 sinx / cosx * cosx
4 tanx / cosx Trig identity tanx = sinx/cosx
C. Teacher would be the correct answer
While A and B often work in . a school environment, a teacher is the best option.
~I hope this helps!~

1) x=9, because we can use the Pythagorean theorem, x^2 + 144 = 225, x^2 = 81
2)
, because 6^2 +6^2 = 72, 
3)
, because 
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