What is the answer to a-4/5 = 12

1. what is the formula for finding the vertical distance between two points on a coordinate plane?

This question awards 100 ! i really don’t want to fail i will also mark you !

What is the multiple zero and multiplicity of f(x) = (x ? 3)(x ? 3)(x + 5)? multiple zero is 3; multiplicity is 2 multiple zero is 5; multiplicity is 1 multiple zero is ? 5; multiplicity is 1 multiple zero is ? 3; multiplicity is 2