(-3, 2) because you take the derivative and youll get y'=2x+6 then solve for x and that is -3 then put -3 in the original equation and you get 2
<h3>
Answer: 78.6</h3>
Work Shown:

Multiply across the rows to form a third column. Example: 9*90 = 810 in the first row.

The values in the third column add to 810+1440+1050 = 3300
Divide this over the total number of people which is 9+18+15 = 42
The mean is 3300/42 =78.571 approximately which rounds to 78.6
Isolate the variable by dividing each side by factors that don't contain the variable. p=q/2r
Sapien because the word homo in homo sapien is the genus name, while the word sapien is the species name.