Question

sketch a rectangle and use the area model to multiply:
$(x + 5)(x + 4)$
$x^2 + 20x + 9$
$x^2 + x + 20$
$x^2 - 9x + 54$
$x^2 + 9x + 20$

Explanation:

Step1: Expand using distributive property

$$(x + 5)(x + 4)=x(x + 4)+5(x + 4)$$

Step2: Distribute again

$$x(x + 4)+5(x + 4)=x^{2}+4x+5x + 20$$

Step3: Combine like terms

$$x^{2}+4x+5x + 20=x^{2}+9x + 20$$

Answer:

\(x^{2}+9x + 20\)