Precalculus: Mathematics for Calculus, 7th Edition

$(2x - 1)(x + 4)$
Separate the middle term into two separate terms that can be factored with the outer terms: $2x^2 + 7x - 4$ $2x^2 + 8x - x - 4$ $2x(x + 4) -1(x + 4)$ $(2x - 1)(x + 4)$