${x}^{2}+3x-5x-15$
Factor out $x$ from the expression$x \times \left( x+3 \right)-5x-15$
Factor out $-5$ from the expression$x \times \left( x+3 \right)-5\left( x+3 \right)$
Factor out $x+3$ from the expression$\left( x+3 \right) \times \left( x-5 \right)$