Part A:
The area of a square is [tex]$(16x^2 - 8x + 1)$[/tex] square units. Determine the length of each side of the square by factoring the area expression completely. Show your work. (5 points)

Part B:
The area of a rectangle is [tex]$(81x^2 - 4y^2)$[/tex] square units. Determine the dimensions of the rectangle by factoring the area expression completely. Show your work. (5 points)



Answer :

### Part A: Factoring the Area of a Square

The area is given by the expression [tex]\( 16x^2 - 8x + 1 \)[/tex]. To find the side length of the square, we need to factor this expression completely.

1. Identify and rewrite the quadratic expression:
[tex]\[ 16x^2 - 8x + 1 \][/tex]

2. Recognize it as a perfect square trinomial: Notice that the expression [tex]\( 16x^2 - 8x + 1 \)[/tex] fits the form [tex]\( (ax + b)^2 \)[/tex].

3. Check for factors:
[tex]\[ (4x - 1)^2 = (4x - 1)(4x - 1) \][/tex]

Expanding [tex]\( (4x - 1)^2 \)[/tex] gives:
[tex]\[ (4x - 1)(4x - 1) = 16x^2 - 8x + 1 \][/tex]

Thus, the factored form of [tex]\( 16x^2 - 8x + 1 \)[/tex] is:
[tex]\[ (4x - 1)^2 \][/tex]

Therefore, the length of each side of the square is [tex]\( 4x - 1 \)[/tex].

### Part B: Factoring the Area of a Rectangle

The area is given by the expression [tex]\( 81x^2 - 4y^2 \)[/tex]. To find the dimensions of the rectangle, we need to factor this expression completely.

1. Identify and rewrite the expression:
[tex]\[ 81x^2 - 4y^2 \][/tex]

2. Recognize it as a difference of squares: The expression [tex]\( 81x^2 - 4y^2 \)[/tex] fits the form [tex]\( a^2 - b^2 \)[/tex], which factors as [tex]\( (a - b)(a + b) \)[/tex].

3. Identify the squares:
[tex]\[ 81x^2 = (9x)^2 \quad \text{and} \quad 4y^2 = (2y)^2 \][/tex]

4. Apply the difference of squares formula:
[tex]\[ 81x^2 - 4y^2 = (9x - 2y)(9x + 2y) \][/tex]

Therefore, the factored form of [tex]\( 81x^2 - 4y^2 \)[/tex] is:
[tex]\[ (9x - 2y)(9x + 2y) \][/tex]

In conclusion, the dimensions of the rectangle are [tex]\( 9x - 2y \)[/tex] and [tex]\( 9x + 2y \)[/tex].