Respuesta :

(7x-1)(4x+5)
(7x)(4x) + (7x)(5) + (-1)(4x) + (-1)(5)
28x^2 + 35x - 4x - 5
28x^2 + 31x - 5

28x^2 + 31x - 5
The answer would be 28x^2+31x-5.