Respuesta :

It's 1849

I'll explain how I found it without actual multiplication,

[tex] {40}^{2} = 1600 \\ {3}^{2} = 9 \\ 2 \times 40 \times 3 = 240 \\ [/tex]

So,

[tex] {43}^{2} = 1600 + 240 + 9 \\ = 1849[/tex]

Hope this will help....