Use the process of factoring by grouping to factor the polynomial. $p ^ { 2 } - 7 p - 3 p + 21$
A) $( p - 3 ) ( p - 7 )$
B) $( p + 3 ) ( p - 21 )$
C) $( p - 3 ) ( p + 7 )$

Question

Quizplus · Accepted Answer

First, group the terms: $p^2 - 7p - 3p + 21 = (p^2 - 7p) - (3p - 21)$. Factoring out the greatest common factor from each group gives $p(p - 7) - 3(p - 7)$. Notice that $(p - 7)$ is a common factor, so the expression can be factored as $(p - 3)(p - 7)$.

Use the Process of Factoring by Grouping to Factor the Polynomial