Answer
[tex]a^{2} -a-12[/tex]
Step-by-step explanation:
One way is to ensure that each term in the second bracket is multiplied by each term in the first bracket, as shown below.
(a+3) - (a - 4)
=a(a−4)+3(a−4)
distribute the brackets.
=[tex]a^{2}[/tex]−[tex]4a[/tex]+[tex]3a[/tex]−12
collecting like terms gives.
= [tex]a^{2}[/tex] − [tex]a[/tex] − 12 ← as a trinomial
