Respuesta :

The square of a sum is:

[tex](a+b)^2=a^2+2ab+b^2[/tex]

using it we have:

[tex]\begin{gathered} (3x+5)^2=(3x)^2+2(3x)(5)+5^2 \\ =9x^2+30x+25 \end{gathered}[/tex]

therefore we have:

[tex](3x+5)^2=9x^2+30x+25[/tex]