Linear Function: Match the Equation to Table Values (-2,4), (-1,2), (1,-2)

Question

Below is a table containing values for x and y. This tables represents a linear function.

Choose the equation that corresponds to the function.

-2-11x42-2y

Video Solution

Step-by-Step Solution

To find the equation of the linear function corresponding to the given table, follow these steps:

  • Step 1: Identify Points
    We have three points from the table: (2,4)(-2, 4), (1,2)(-1, 2), and (1,2)(1, -2).
  • Step 2: Calculate the Slope
    The slope mm can be calculated using any two points. Choosing (2,4)(-2, 4) and (1,2)(-1, 2):
    m=y2y1x2x1=241(2)=21=2 m = \frac{y_2 - y_1}{x_2 - x_1} = \frac{2 - 4}{-1 - (-2)} = \frac{-2}{1} = -2 .
  • Step 3: Verify Linear Relationship
    Using (x,y)(x, y) pairs, check another pair such as (1,2)(-1, 2) and (1,2)(1, -2):
    m=221(1)=42=2 m = \frac{-2 - 2}{1 - (-1)} = \frac{-4}{2} = -2 .
  • Step 4: Select the Correct Equation
    The slope is 2-2, and since a linear function typically can be formatted as y=mx+by = mx + b, we can see if b=0b = 0 by trying one of the equations y=2xy = -2x given in the choices. Let’s check:
    For x=2x = -2: y=2(2)=4y = -2(-2) = 4. Matches.
    For x=1x = -1: y=2(1)=2y = -2(-1) = 2. Matches.
    For x=1x = 1: y=2(1)=2y = -2(1) = -2. Matches.
  • Therefore, the equation that corresponds to the function is y=2x y = -2x .

Answer

y=2x y=-2x