Express as a trinomial (x+9)(3x+9)

Answer 1

to FOIL (x+9)(3x+9): Start with the "firsts" (x)(3x) = 3x²

Next, do the "outsides" (x)(9) = 9x

Then, do the "insides" (9)(3x)= 27x

Lastly, do the "lasts" (9)(9)= 81

Then add all the "answers" together : 3x²+9x+27x+81

Your final step is then to simplify the equation: 3x²+36x+81