Use SOH CAH TOA to identify the Tangent Z.

SOH = Sine Opposite Hypotenus

CAH = Cosine Adjacent Hypotenus

TOA = Tangent Opposite Adjacent

Based on the key I wrote above, TOA is what you will use. Starting from angle Z look at the opposite side and adjacent side. (Opposite = 21 and Adjacent = 20) Make sure you're not looking at the hypotenus which is the side that is always across from the 90° angle.

Going by opposite over adjacent, that would be 21/20

The answer is the first choice 21/20

y = 2x

step-by-step explanation:

if you divide each number in the sequence, you'll see that they all have a multiple factor of 2. each number in the series, and any other numbers which may continue, will be multiplied by 2. therefore, y is the next number in the sequence, and x is the current one, so, our formula will be y = 2x.

a and c

step-by-step explanation: