All the options are incorrect, if you're talking about circle! which is most common
C = 2πr..... It is the relation for Circle's if you're considering something else, then, please mention!
Answer:
x=60.56, x=-82.56
Step-by-step explanation:
Solve using quadratic formula
Formula is

0.05x^2 + 1.1x = 250
Subtract 250 on both sides
0.05x^2 + 1.1x - 250=0
a= 0.05, b=1.1 , c=-250
Plug in the values in the formula


Now make two equations , one with + and one with -
then we solve for x

x=60.56

x=-82.56
The correct answer is C my friend
Step-by-step explanation:
98 = 188t - 16t^2
-16t^2 + 188t = 98
-16t^2 + 188t - 98 = 0
8t^2 - 94t + 49 = 0
Use the quadratic formula with a = 8 , b = -94 , c = 49 to get the solutions
t = [(47 - root 1817) / 8]≈ 0.55
and
t = [(47 + root 1817) / 8] ≈ 11.20