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