Answer:
[tex] {x}^{2} + 9x + 20[/tex]
Step-by-step explanation:
1) Use FOIL method: (a + b) (c + d) = ac + ad + bc + bd.
[tex] {x}^{2} + 5x + 4x + 20[/tex]
2) Collect like terms.
[tex] {x}^{2} + (5x + 4x) + 20[/tex]
3) Simplify.
[tex] {x}^{2} + 9x + 20[/tex]
Therefor, the answer is x² + 9x + 20.
