Question

If you factor y^2-81 COMPLETELY, would it just be (y-9)(y+9), or would it be something like y(3)(-3)y(3)(3)?

Answer 1

That would be (y - 9)(y +9). When two binomials are multiplied, the distributive property is applied. However, if the equation is y(3)(-3)y(3)(3), you just simply multiply them altogether. That would be -81y^2, which is not equivalent with y^2 - 81.