Respuesta :
a^2+b^2=c^2
21^2+20^2=c^2
441+400=c^2
841=c^2
square root on both sides to get the variable by itself
29=c
21^2+20^2=c^2
441+400=c^2
841=c^2
square root on both sides to get the variable by itself
29=c
Answer:
29
Step-by-step explanation:
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