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