Respuesta :

Answer:

12^2 + 43x + 35

Step-by-step explanation:

(3x+7)(4x+5)

=(3x+7)(4x+5)

=(3x)(4x)+(3x)(5)+(7)(4x)+(7)(5)

=12x2+15x+28x+35

=12x2+43x+35