Respuesta :

I know the 1st one.

Answer:

(x+3)(x-4) = x-12

Step-by-step explanation:

This is called a foil method

1st: We multiply the two first numbers - x*x = 2x

2nd: We multiply the two outside numbers - x*(-4) = -4x

3rd: We multiply the two inside numbers - 3*x = 3x

4th: We multiply the two last numbers - 3*(-4) = -12

Then we combine them - 2x-4x+3x-12

Then we simplify - x-12

Hope this helped!