Question

Given the diagram below, what is sin (30°) ?

Answer 1

Answer:

A.  1/2.

Step-by-step explanation:

The ratio of the sides of a 30-60-90 triangle  is 2:1:√3   where  2 is the hypotenuse. 1 is the shortest leg and √3 is the longest leg.

In the diagram we see that the longest leg is opposite the 60 degree angle.

So the longest leg is 3.5√x and  the shortest leg ( from applying the ratios) = 3.5√x / √3.

and the hypotenuse is  2 *  3.5√x / √3    (using the ratios again).

So sin  30 = shortest leg / hypotenuse =  3.5√x / √3 /  2 *  3.5√x / √3

= 1/2.