Is this equation linear or nonlinear? 5xy + 4 = 9

5xy+4=9

5xy=5

xy=1

y=1/x

So this is of the form kx^ (-1), this is not linear as the rate of change is not constant ... only kx^1 will have a constant rate of change and be linear.

If you graph it you will see that it is exponential ... definitely not a straight line : P

It is definitely linear