Question

factor the expression by grouping: $5x^2 + 10x - 8x - 16$
$(5x + 8)(x - 2)$
$(5x + 2)(x - 8)$
$(5x - 8)(x + 2)$
$(5x - 2)(x + 8)$

Explanation:

Step1: Group the terms

Group the first two terms and the last two terms: $(5x^2 + 10x) + (-8x - 16)$

Step2: Factor out the GCF from each group

Factor out $5x$ from the first group and $-8$ from the second group: $5x(x + 2) - 8(x + 2)$

Step3: Factor out the common binomial factor

Factor out $(x + 2)$: $(5x - 8)(x + 2)$

Answer:

$(5x - 8)(x + 2)$ (corresponding to the option: (5x - 8)(x + 2))