Answer:
[tex] {x}^{2} + 18x + 81[/tex]
Step-by-step explanation:
[tex](x + 9) {}^{2} [/tex]
Apply foil method.
[tex](x + 9) {}^{2} = (x + 9)(x + 9)[/tex]
Multiply the first terms, X
[tex]x \times x = {x}^{2} [/tex]
Multiply outer terms, 9 and x.
[tex]x \times 9 = 9x[/tex]
Multiply inner terms,
[tex]9 \times x = 9x[/tex]
Multiply outer terms.
[tex]9 \times 9 = 81[/tex]
Add the inner and outer terms
[tex]9x + 9x = 18x[/tex]
Write in standard form
[tex] {x}^{2} + 18x + 81[/tex]
