Question

Write a simplified polynomial expression in standard form to represent the area of the rectangle below.

Answer 1

Answer:

The correct option is C.

Step-by-step explanation:

Given information: One side of the rectangle is (5x+2) and another sides of rectangle is (x-4).

The area of rectangle is

$A=length \times width$

Substitute length = (5x+2) and width = (x-4) in the above formula, to find the simplified polynomial expression in standard form to represent the area of the rectangle.

$A=(5x+2)\times (x-4)$

Using distributive property,

$A=5x(x-4)+2(x-4)$

$A=5x(x)+5x(-4)+2(x)+2(-4)$

On simplification we get

$A=5x^2-20x+2x-8$

On combining like terms we get

$A=5x^2+(-20x+2x)-8$

$A=5x^2+(-18x)-8$

$A=5x^2-18x-8$

Therefore the correct option is C.

Answer 2

(5x+2)(x-4
5x (x)+2(x)+5x (-4)+2 (-4)
5x^2+2x-20x-8
5x^2-18x-8
C. 5x^2-18x-8