First let us convert 0.01 into fraction:
[tex] \frac{y^{2}}{100} -\frac{1}{4} [/tex]
Now we convert 100 and 4 into perfect squares as follows:
[tex] (\frac{y}{10})^{2}-(\frac{1}{2})^{2} [/tex]
Now we use the property of :
[tex] x^{2} -y^{2} =(x+y)(x-y) [/tex]
[tex] (\frac{y}{10} +\frac{1}{2} ) (\frac{y}{10} -\frac{1}{2} ) [/tex]