The trig function sine, often abbreviated as "sin" (pronounced the same way as "sine"), is essentially the ratio or fraction of the opposite side and the hypotenuse. See the attached image for a reference.
The leg opposite angle B is side AC. Note how B is not present in the sequence "AC". Visually, we are as far away as possible from point B. This side is 16 units long. So AC = 16
The hypotenuse is the longest side of the right triangle. Always always always. This longest side is opposite the largest angle (90 degrees). Therefore the hypotenuse is BC = 17.46
In summary so far, we have,
opposite side = AC = 16
hypotenuse BC = 17.46
Let's use those values to compute sin(B)
sin(Angle) = opposite/hypotenuse
sin(B) = AC/BC
sin(B) = 16/17.46
sin(B) = 0.916 (this is approximate)
sin(B) = 0.92 (rounding to nearest hundredth)
This points to the final answer of choice A) 0.92
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Edit: Sorry nearly forgot about the reference image. I attached it just now.
The leg opposite angle B is side AC. Note how B is not present in the sequence "AC". Visually, we are as far away as possible from point B. This side is 16 units long. So AC = 16
The hypotenuse is the longest side of the right triangle. Always always always. This longest side is opposite the largest angle (90 degrees). Therefore the hypotenuse is BC = 17.46
In summary so far, we have,
opposite side = AC = 16
hypotenuse BC = 17.46
Let's use those values to compute sin(B)
sin(Angle) = opposite/hypotenuse
sin(B) = AC/BC
sin(B) = 16/17.46
sin(B) = 0.916 (this is approximate)
sin(B) = 0.92 (rounding to nearest hundredth)
This points to the final answer of choice A) 0.92
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Edit: Sorry nearly forgot about the reference image. I attached it just now.