PLEASE HELP ...... .....

Answer:
2√2
Step-by-step explanation:
since this is a right triangle and the two legs are congruent, b must also equal 2
then using pythagorean theorem (a^2 + b^2 = c^2), we can find that a = 2√2
I hope this helped, and if my answer was right, please mark this answer as brainliest! Thank you!