For an equation to be a function, you can only get one output (y) for any input (x). Now let's test. Create fast table of values using 5 sample inputs (x's) like -2,-1,0,1, 2. Put each x into the equation and solve for y. Use the ordered pairs to sketch a graph.Now apply the vertical line test. If a vertical line drawn anywhere can intersect your graphed line at only one point, you have a function Each x you put in resulted in a unique y output! Good Luck.