## Precalculus: Concepts Through Functions, A Unit Circle Approach to Trigonometry (3rd Edition)

$(x+2)(3x+4)$
First, for the polynomial $3x^2 + 10x + 8$, we write $$3x^2 + 10x + 8=3x^2 + 6x +4x+ 8 .$$ By grouping the first two terms and the second two terms and then taking common factors, we have $$3x^2 + 6x +4x+ 8=3x(x+2)+4(x+2)=(x+2)(3x+4) .$$