How is times the sum of eight and a number is solved?

An equation of the line tangent to y=x^3+3x^2+2 at its point of inflection is

Ricky takes out a $31,800 student loan to pay his expenses while he is in college. after graduation, he will begin making payments of $190.66 per month for the next 30 years to pay off the loan. how much more will ricky end up paying for the loan than the original value of $31,800? ricky will end up paying $ more than he borrowed to pay off the loan.

Someone me what is the area of this figure? 18m 18m 8m 16m