Question

Geometry math question

Answer 1

Remaining leg = 21 * sq root (3)
Angle opposite length 21 leg is 30 degrees.

Source:
http://www.1728.org/trig2.htm

Answer 2

Let's solve for the other leg length
a^2 + 21^2 = 42^2
a^2 + 441 = 1764
subtract 441 from both sides
a^2 = 1323
take the square root of both sides
a = sqrt.(1323)
a = 21 sqrt.(3)

The correct answer is C.) The length of the remaining leg is 21 sqrt.(3).

Hope this helps