If the legs are length a and b and hyptonuse is c then
a²+b²=c²
so
if the legs are 20 and 21 and the hypotnuse is x then
20²+21²=x²
400+441=x²
841=x²
29=x
Travels by 2 so therefore the answer is B
C = 5(F-32)/9 Multiply each side by 9
9C = 5(F-32) Distribute
9C = 5F - 160 Add 160 to each side
9C + 160 = 5F Divide each side by 5
9/5C + 32 = F