I need help :( I don't know how to do it

The graph of a function f(x)=(x+2)(x-4). which describes all of the values for which the graph is negative and increasing? all real values of x where x< -2 all real values of x where -2

Estimate the area under the curve f(x) = 16 - x^2 from x = 0 to x = 3 by using three inscribed (under the curve) rectangles. answer to the nearest integer.

6x + 3y = -6 2x + y = -2 a. x = 0, y = -2 b. infinite solutions c. x = -1, y = 0 d. no solution