Question

Expand $(x-3)(x-19)$.

• A. $x^2+22x+57$
• B. $x^2-22x-57$
• C. $x^2-22x+57$
• D. $x^2+22x-57$

Answer 1

The correct option is C $x^2-22x+57$

Using the identity,

$(x-a)(x-b)=x^2-(a+b)x+ab$

$(x-3)(x-19)=x^2-(3+19)x+\left(3\right)\left(19\right)$

= $x^2-22x+57$