(1B) The product $(a+b)(c+d)$
Practice
Expand and simplify.
*Write your answers with powers of $x$ in descending order. $\left(\square x^2 \pm \square x \pm \square\right)$
$\left(x-7\right)\left(x-3\right)$
$\left(x+4\right)\left(x+6\right)$
$\left(x+3\right)\left(-8+x\right)$
$\left(x-5\right)\left(6+x\right)$
$\left(7-x\right)\left(-x+7\right)$
$\left(-9+x\right)\left(x-5\right)$
$\left(9-x\right)\left(5-x\right)$
$\left(3+x\right)\left(5-x\right)$
$\left(7x-4\right)\left(4x-5\right)$
$\left(-x+6\right)\left(-5x+2\right)$
$\left(2x-1\right)\left(-5+6x\right)$
$\left(-3x+2\right)\left(5+3x\right)$
$\left(4-7x\right)\left(4x+1\right)$
$\left(1+2x\right)\left(2x-9\right)$
$\left(-7+3x\right)\left(-3+7x\right)$
$\left(1+7x\right)\left(-1+4x\right)$