Respuesta :

Answer:

25x^2 +40x+16

Step-by-step explanation:

(5x + 4)²​

(5x+4)(5x+4)

FOIL

first  5x*5x = 25x^2

outer  5x*4 = 20x

inner 4*5x = 20x

last = 4*4 = 16

Add them together

25x^2 +20x+20x+16

Combine like terms

25x^2 +40x+16

Answer:

[tex] {(5x + 4)}^{2} \\ = {(5x)}^{2} + 2 \times 4 \times 5x + {4}^{2} \\ = 25 {x}^{2} + 40x + 16 \\ thank \: you[/tex]