In order to find the factors of 15, let's write this number as a product of two number x and y, representing the area of a rectangle:
[tex]15=x\cdot y[/tex]Then, choosing natural values for x and calculating y, we have:
[tex]\begin{gathered} x=1\colon y=\frac{15}{1}=15 \\ x=2\colon y=\frac{15}{2}=7.5 \\ x=3\colon y=\frac{15}{3}=5 \\ x=4\colon y=\frac{15}{4}=3.75 \\ x=5\colon y=\frac{15}{5}=3 \end{gathered}[/tex]We can see that the only pair of numbers that are both natural (besides 1 and 15) are the numbers 3 and 5.
Therefore the factors of 15 are 3 and 5.
