Answer
(a.) $6x^2+33x+15$
(b.) $27+33\sqrt2$.
Work Step by Step
(a.) The given expression is
$=(x+5)(6x+3)$
Use the FOIL method.
$=6x^2+3x+30x+15$
Simplify.
$=6x^2+33x+15$
(b.) The given expression is
$=(\sqrt2+5)(6\sqrt2+3)$
Use the FOIL method.
$=6\sqrt2\cdot \sqrt2+3\sqrt2+30\sqrt2+15$
Simplify.
$=6\cdot 2+33\sqrt2+15$
$=12+33\sqrt2+15$
$=27+33\sqrt2$.
