What is the value of 2x^3+x^2-x when x=3?

What are “like terms”? why can we only add like terms?

Scores on a university exam are normally distributed with a mean of 78 and a standard deviation of 8. the professor teaching the class declares that a score of 70 or higher is required for a grade of at least “c.” using the 68-95-99.7 rule, what percentage of students failed to earn a grade of at least “c”?

Suppose m: angle a =77 degrees what is the measure of a complement of a complement of angle a, what is a conclusion you can draw about a complement of a complement of an angle