How do I find where the function is decreasing?

Geometry in the diagram, ∠abc is a right angle. ∠dbc = 30°27'40". find the measure of ∠abd.

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

Factor the trinomial below. 12x^2 - 32x - 12 a. 4(3x+3)(x-1) b. 4(3x+1)(x-3) c. 4(3x+6)(x-2) d. 4(3x+2)(x-6)