Question

Factorise y^2 - 169?????????????

Answer 1

Step 1. Rewrite it in the form:
`a^(2) - b^(2)`, where a = y and b = 13


`y^(2) - 13^(2)`

Step 2. Use Difference of Squares:
`a^(2) - b^(2) =(a+b)(a-b)`


`(y+13)(y-13)`

Done!

Answer 2

= y^2 - 169
= (y)^2 - (13)^2
= (y + 2)(y - 2)