Mentally factor the trinomial $a ^ { 2 } + a - 56$
A) $( a - 7 ) ( a + 8 )$
B) $( a + 7 ) ( a - 8 )$
C) $( a - 7 ) ( a - 8 )$
D) $( a - 4 ) ( a + 14 )$
E) $( a + 4 ) ( a - 14 )$

Question

Quizplus · Accepted Answer

The correct factorization of $a^2 + a - 56$ is found by looking for two numbers that multiply to -56 and add to 1. The numbers -7 and 8 fit this criteria, so the factorization is $(a - 7)(a + 8)$.

Mentally Factor the Trinomial a2+a−56a ^ { 2 } + a - 56a2+a−56

Mentally Factor the Trinomial $a ^ { 2 } + a - 56$