b= 63 and that is your answer
59.4cm
Use Pythagorean theorem to find the diagonal (^ means exponent)
a^2 + b^2 = c^2
42^2 + 42^2= c^2
1764+1764=c^2
3528=c^2
square root both sides
c= 59.39696962
round and you get 59.4 cm
Answer:
for every 2 tables there are 10 chairs, so for 12 tables there are 60 chairs
Sin C= 3/5
Your answer would be A