Respuesta :

The first one is x^2 -9x +20
The second one is x^2 -12x +20
The third one is x^2 +x -20
The fourth one is x^2 - 8x -20

Answer:

1) a²-9a+20

2)a²-12a+20

3)a²+a-20

4)a²-8a-20

Step-by-step explanation:

use (foil)

front

outside

inside

last