12)
Look at the graph, here : https://www.desmos.com/calculator/wfs9ho2uyr
The graph increases from (-infinity, -4) and from (-4/3, infinity)
The graph decreases from (-4, -4/3)
13)
Look at the graph, here : https://www.desmos.com/calculator/n6ss75kmnc
The graph increases from ( -infinity, -1) and from (-.366 , 1.366)
The graph decreases from ( -1, -.366) and from (1.366, infinity)