We have these three functions: y=15 [tex]y=3-x^3[/tex] y=11+5x
First, let's look at y=15. If you graph this, this is just a horizontal line with a y value of 15. Thus, the first function is linear.
Next, let's look at [tex]y=3-x^3[/tex] Notice that this function has an x to a power of 3. Since this power is greater than 1, this cannot be linear. Thus, the second function is nonlinear.
Finally, let's look at y=11+5x. Let's change the order of the 11 and 5x. We get y=5x+11. This function is in the form of y=mx+b, which is the slope-intercept form of a line (where m is the slope and b is the y-intercept). Thus, the last function is linear.
