Multiply: (2x + 8) by (x − 3)

To multiply the expressions, we will use the distributive law in the following way:

$(2 x+8)(x-3)$

$=2 x(x-3)+8(x-3)$

$=(2 x \times x-2 x \times 3)+(8 x-8 \times 3)$

$=\left(2 x^{2}-6 x\right)+(8 x-24)$

$=2 x^{2}-6 x+8 x-24$

$=2 x^{2}+2 x-24$

Thus, the answer is $2 x^{2}+2 x-24$.