Question

Answer 1

2: \(x^2-5=\left(x-\sqrt{5}\right)\left(x+\sqrt{5}\right)\)

3: \(x^3-9x=x\left(x-3\right)\left(x+3\right)\)

4: \(x^2-y^2-6x+9=\left(x-3-y\right)\left(x-3+y\right)\)

5: \(x^2-y^2-5x+5y\)

\(=\left(x-y\right)\left(x+y\right)-5\left(x-y\right)\)

\(=\left(x-y\right)\left(x+y-5\right)\)