Hassan wants to add a border to a photo he took before he frames it. The final area of the entire framed picture will be 96 square inches. The length of the picture is 10 inches, and the width is 6 inches. Which of the following is the width of the border?(1 point)

Responses

3 inches
3 inches

1 inch
1 inch

4 inches
4 inches

9 inches

1 answer

To determine the width of the border, we start by calculating the area of the picture without the border.

The area of the picture is given by: \[ \text{Area} = \text{length} \times \text{width} = 10 , \text{inches} \times 6 , \text{inches} = 60 , \text{square inches}. \]

The total area of the entire framed picture, including the border, is given as 96 square inches.

Let \( x \) be the width of the border. The dimensions of the framed picture with the border will be:

  • Length: \( 10 + 2x \) (adding the border on both sides)
  • Width: \( 6 + 2x \) (adding the border on both sides)

The area of the framed picture can be expressed as: \[ \text{Total Area} = (10 + 2x)(6 + 2x). \] We set this equal to 96 square inches: \[ (10 + 2x)(6 + 2x) = 96. \]

Now, we expand the left-hand side: \[ 60 + 20x + 12x + 4x^2 = 96, \] which simplifies to: \[ 4x^2 + 32x + 60 = 96. \]

Subtract 96 from both sides: \[ 4x^2 + 32x + 60 - 96 = 0, \] which simplifies to: \[ 4x^2 + 32x - 36 = 0. \]

Dividing the entire equation by 4: \[ x^2 + 8x - 9 = 0. \]

Now we can factor the quadratic equation: \[ (x + 9)(x - 1) = 0. \]

This gives us two solutions: \[ x + 9 = 0 \quad \Rightarrow \quad x = -9 \quad (\text{not valid}), \] \[ x - 1 = 0 \quad \Rightarrow \quad x = 1. \]

The valid width of the border is \( x = 1 \) inch.

Thus, the width of the border is 1 inch.