Apply distributive property: Apply the distributive property (also known as the FOIL method) to multiply the two binomials (x−9) and (2x−9). First, multiply the first terms in each binomial: x×2x=2x2.
Multiply first terms: Multiply the outer terms: x×(−9)=−9x.
Multiply outer terms: Multiply the inner terms: (−9)×2x=−18x.
Multiply inner terms: Multiply the last terms in each binomial: (−9)×(−9)=81.
Multiply last terms: Combine the like terms from the products of the outer and inner terms: −9x−18x=−27x.
Combine like terms: Write the simplified trinomial expression by combining all the products: 2x2−27x+81.