Answer
$12x^2-x-35$
Work Step by Step
RECALL:
(1) $(a+b)(c+d) = a(c+d) + b(c+d)$
(2) $a(b+c) = ab+ac$
Use rule (1) above to obtain:
$=3x(4x-7)+5(4x-7)$
Use rule (2) above to obtain:
$=3x(4x) -3x(7) + 5(4x) -5(7)
\\=12x^2-21x+20x-35$
Combine like terms to obtain:
$=12x^2-x-35$
