Answer:
D. 20/29
Step-by-step explanation:
The sine of an angle in a right triangle is the ratio between the side opposite to the angle and the side adjacent to the angle, or [tex]sin(a) = \frac{opposite}{hypotenuse}[/tex]. The hypotenuse is the longest side of a right triangle.
In this case, the opposite side has length 20, and the hypotenuse has length 29. Therefore, the answer is
[tex]sin(a) = \frac{20}{29}[/tex].
To remember this (and the other trigonmetric ratios), you can use the acronym SOCAHTOA, where
SOH is sin(a) = opposite/hypotenuse
CAH is cos(a) = adjacent/hypotenuse
TOA is tan(a) = opposite/adjacent
