y^2-64

So here its similar principle to the previous question but the only difference is that there are no singular y's.So essentially the question reads : y^2 + 0y - 64So in the same way we need factors of 64 that multiply to give -64 and add to give 0. The only way that happens is if the number is the same. I.E. 8 would be the factor we use. Since we need MINUS 64. One 8 is positive and one negative:In this way we can see how the two 8's will cancel each other out to give 0 y so the brackets will read:(y-8)(y+8)Check this by expanding the brackets.This form of factorising quadratics is known as DOTS: Difference Of Two Squares.Once the method is understood- it is easy to spot these as both variables have whole square roots. So you can then do q's like y^2-25, or 4x^2- 36