Respuesta :

Answer:

C) 21

Step-by-step explanation:

a² + 20² = 29²       Use Pythagorean Theorem to solve for a

a² + 400 = 841       Solve for the exponents

     - 400 - 400      Subtract 400 from both sides

a² = 441                  Take the square root of both sides

a = 21

Answer:

the answer is C. 21

Step-by-step explanation: