Which equations are true identities

Which expression is the factored from of 2/3x + 4?asap

Suppose that the price p (in dollars) and the weekly sales x (in thousands of units) of a certain commodity satisfy the demand equation 4p cubedplusx squaredequals38 comma 400. determine the rate at which sales are changing at a time when xequals80, pequals20, and the price is falling at the rate of $.20 per week.

Valentina is subtracting from . she finds the lcd to be 15y2. what is valentina's next step?