Use a graphing calculator to graph the original function y=1/2x−4

and the vertically dilated function with a factor k=6
. Determine the x-intercepts of both functions.(1 point)
Responses

The original function has an x-intercept of (−8,0)
, and the dilated function has an x-intercept of (−8,0)
.
The original function has an x -intercept of left parenthesis negative 8 comma 0 right parenthesis , and the dilated function has an x -intercept of left parenthesis negative 8 comma 0 right parenthesis .

The original function has an x-intercept of (8,0)
, and the dilated function has an x-intercept of (8,0)
.
The original function has an x -intercept of left parenthesis 8 comma 0 right parenthesis , and the dilated function has an x -intercept of left parenthesis 8 comma 0 right parenthesis .

The original function has an x-intercept of (8,0)
, and the dilated function has an x-intercept of (48,0)
.
The original function has an x -intercept of left parenthesis 8 comma 0 right parenthesis , and the dilated function has an x -intercept of left parenthesis 48 comma 0 right parenthesis .

The original function has an x-intercept of (0,−4)
, and the dilated function has an x-intercept of (0,−24)
.

1 answer

To find the x-intercepts of the functions given, we need to set \( y = 0 \) and solve for \( x \).

  1. Original function: \( y = \frac{1}{2}x - 4 \)

    • Set \( y = 0 \): \[ 0 = \frac{1}{2}x - 4 \]
    • Solve for \( x \): \[ \frac{1}{2}x = 4 \quad \Rightarrow \quad x = 4 \times 2 = 8 \]
    • Thus, the x-intercept of the original function is \( (8, 0) \).
  2. Vertically dilated function with a factor of \( k = 6 \):

    • The equation transforms to \( y = k \cdot \left(\frac{1}{2}x - 4\right) = 6 \cdot \left(\frac{1}{2}x - 4\right) \) or \( y = 3x - 24 \).
    • Set \( y = 0 \): \[ 0 = 3x - 24 \]
    • Solve for \( x \): \[ 3x = 24 \quad \Rightarrow \quad x = \frac{24}{3} = 8 \]
    • Thus, the x-intercept of the dilated function is also \( (8, 0) \).

Therefore, both functions have the same x-intercept:

Original function: \( (8, 0) \)
Dilated function: \( (8, 0) \)

The correct response is: "The original function has an x-intercept of (8,0), and the dilated function has an x-intercept of (8,0)."