Answer:
The answer is x² + x - 12.
Step-by-step explanation:
1) Use foil method: (a + b) (c + d) = ac + ad + b + bd.
[tex] {x}^{2} - 3x + 4x - 12[/tex]
2) Collect like terms.
[tex] {x}^{2} + ( - 3x + 4x) - 12[/tex]
3) Simplify.
[tex] {x}^{2} + x - 12[/tex]
hence, the answer is x² + x - 12.
