Walk rightward along x and where the graph climbs it's increasing, where it slides down it's decreasing; bigger x giving bigger y is what we call an increasing function.
Module goal. Learn to capture a function's rise and fall, symmetry, and high and low points from both the graph and the symbols, getting ready to analyze linear functions
eastmath.com · 20.6 Reading a Function's Behavior off Its Graph · 20.6.1 Monotonicity: Going Up and Going Down