Help? I don’t know which is right

C

Step-by-step explanation:

Given

tanθ = =

This is a right triangle with legs 1 and 2

Using Pythagoras' identity

hypotenuse² = 1² + 2² = 1 + 4 = 5 ( take square root of both sides )

hypotenuse =

θ is in the 3rd quadrant where sinθ < 0 , then

sinθ = = - ← rationalise the denominator

       = - ×

       = - → C

828. all there is to it!

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c) yes, because of asa or aas