Yes, borh ratios when reduced are 5:2. 30:12 is 5:2 because both are divisible by 6. 30/6=5 and 12/6=2. 40:16 is 5:2 because both are divisible by 8, 40/8=5 and 16/8=2
just look at the length to the side of it (the "28") and look at the given answers. 4 seems way too small and because the line is shorter than 28 it cant be 43, so 16.8 is the most reasonable option.
As we notice, tanθ is a fraction. Fractions are undefined when the denominator is equal to or approaching 0 because one cannot divide by zero. Thus, the denominator in this case is cosθ, and therefore it cannot equal zero for the equation to be true.
