A solution set of the equation 5 sin(theta)+ 3 = 3 contains all multiples of
(a) 45 degrees
(b) 90 degrees
(c) 135 degrees
(d) 180 degrees
Well, first we have to isolate the $\displaystyle \sin {\theta}$
$\displaystyle 5 \sin {\theta} +3 = 3$
subtract 3 from both sides to get
$\displaystyle 5 \sin {\theta)=0$
divide both sides by 5
$\displaystyle \sin {\theta} = 0$
Now, for what $\displaystyle \theta$ does $\displaystyle \sin {\theta} = 0$? That is true at all multiples of 180 degrees so d is your answer.