# How do you simplify (3x+5)(x-3) ?

$3 {x}^{2} - 4 x - 15$
To multiply these polynomials, take $3 x$ and multiply it by $x$ and $- 3$ and do the same to $5$. After you multiplied the polynomials, combine the like terms.
$\left(3 x + 5\right) \left(x - 3\right)$
$3 {x}^{2} - 9 x + 5 x - 15$
$3 {x}^{2} - 4 x - 15$