For this case, we have that by definition, the circumference of a circle is given by:

Where:
d: Is the diameter of the circle given by 2r, that is, twice the radius.
If we have a circle with a diameter equal to 8cm, then the circumference is given by:

ANswer:
Option C

Either the 4th answer or 1st one
Answer:
C. Solving this equation results in the statement –48 = 48. Because this is a false statement, the equation has no solution.
X² + 11x + 28 + x² + 13x + 40
combine like terms
x² + x² = 2x²
11x + 13x = 24x
28 + 40 = 68
2x² + 24x + 68 is your answer
if you want it simplified:
2(x² + 12x + 34)
hope this helps