Please help me find the value of X please!

Me ! write an equation for the interior angles of this triangle that uses the triangle sum theorem

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

The roots of the function f(x) = x2 – 2x – 3 are shown. what is the missing number?