Question

3. The area of a rectangular deck, in square meters, is given by the polynomial 40p2 + 24p.

The deck is 8p meters wide.
a) Find the polynomial that represents the length of the deck.
b) Find the polynomial that represents the perimeter of the deck.

Answer 1

Length = 5p + 3

Perimeter = 26p + 6

Explanation:

Given

Area = 40p² + 24p

Width = 8p

Solving for the length of deck

Given that the deck is rectangular in shape.

The area will be calculated as thus;

Area = Length * Width

Substitute 40p² + 24p and 8p for Area and Width respectively

The formula becomes

40p² + 24p = Length * 8p

Factorize both sides

p(40p + 24) = Length * 8 * p

Divide both sides by P

40p + 24 = Length * 8

Factorize both sides, again

8(5p + 3) = Length * 8

Multiply both sides by ⅛

⅛ * 8(5p + 3) = Length * 8 * ⅛

5p + 3 = Length

Length = 5p + 3

Solving for the perimeter of the deck

The perimeter of the deck is calculated as thus

Perimeter = 2(Length + Width)

Substitute 5p + 3 and 8p for Length and Width, respectively.

Perimeter = 2(5p + 3 + 8p)

Perimeter = 2(5p + 8p + 3)

Perimeter = 2(13p + 3)

Open bracket

Perimeter = 2 * 13p + 2 * 3

Perimeter = 26p + 6