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PLEASE PLEASE HELP DUE TMRW !!!

A room has dimensions as shown.

3x (height)
4x +3 (length)

a) Find a simplified expression for the perimeter.

b) Find a simplified expression for thearea.

c) Repeat parts a) and b) if both the
length and width are doubled.

d) Has this doubled the perimeter?
Justify your answer.

e) Has this doubled the area? Justify your answer.

User Avnish
by
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1 Answer

6 votes

Answer:

a) The perimeter of the room is the sum of the lengths of all four sides. The length of two opposite sides is 4x + 3, and the length of the other two opposite sides is 3x. Therefore, the perimeter is:

P = 2(4x + 3) + 2(3x) = 14x + 6

b) The area of the room is the product of the length, width, and height. The length is 4x + 3, the width is 3x, and the height is 3x. Therefore, the area is:

A = (4x + 3)(3x)(3x) = 27x^2 + 12x

c) If both the length and width are doubled, the new dimensions are 2(4x + 3) = 8x + 6 for the length and 2(3x) = 6x for the width.

a) The new perimeter is the sum of the lengths of all four sides:

P' = 2(8x + 6) + 2(6x) = 28x + 12

b) The new area is the product of the length, width, and height:

A' = (8x + 6)(6x)(3x) = 144x^2 + 72x

d) The new perimeter is not twice the original perimeter because:

P' = 28x + 12

2P = 28x + 12 + 28x + 12 = 56x + 24

Therefore, 2P is not equal to P', so doubling the length and width does not double the perimeter.

e) The new area is not twice the original area because:

A' = 144x^2 + 72x

2A = 2(27x^2 + 12x) = 54x^2 + 24x

Therefore, 2A is not equal to A', so doubling the length and width does not double the area.

User Anudeep Gade
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8.7k points