#### Answer

$x^{2}$ + 8x+15

#### Work Step by Step

Two binomials can be quickly multiplied by using the FOIL method, in which F represents the product of the first terms in each binomial, O represents the product of the outside terms, I represents the product of the two inside terms, and L represents the product of the last,
(x+3)(x+5)
F = x.x = $x^{2}$
O = x.5 = 5x
I = 3.x = 3x
L = 3.5 = 15
(x+3)(x+5) = $x^{2}$ + 5x+3x+15
combine like terms
$x^{2}$ + 8x+15