PLEASE HELP I RESLLY NEED IT SHOW WORK BRAINLIEST AND 20 POINTS

MY GUESS: =====C: 4 inch
Step-by-step explanation:
12^2 + B^2 = 20^2
144+B^2 =400
200-144 = 56 = B^2
B^2 = 7.48331477355
7.48331477355 - 3 = 4ish inches
Answer:
[tex]i \: think \: 4 \: inches[/tex]
I hope it helps
have a nice day
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