Line

j is shown on the coordinate grid. The table of ordered pairs represents some points on line
k.

x: -1,0,1,2
y: 8,5,2,-1
Which system of equations represents the line
j and line k?

1 answer

To find the equations representing line \( j \) and line \( k \), we first need to derive the equation for line \( k \) using the ordered pairs provided in the table:

  • Points on line \( k \):
    • \((-1, 8)\)
    • \((0, 5)\)
    • \((1, 2)\)
    • \((2, -1)\)

Step 1: Determine the slope of line \( k \)

The slope (\( m \)) can be found using any two points on line \( k \). Let's take the first two points: \((-1, 8)\) and \((0, 5)\).

The formula for slope is:

\[ m = \frac{y_2 - y_1}{x_2 - x_1} \]

Substituting the points:

\[ m = \frac{5 - 8}{0 - (-1)} = \frac{-3}{1} = -3 \]

Step 2: Write the point-slope form of the equation

Now, we can use the point-slope form of the equation of a line, which is:

\[ y - y_1 = m(x - x_1) \]

Using the point \((0, 5)\):

\[ y - 5 = -3(x - 0) \]

This simplifies to:

\[ y - 5 = -3x \ y = -3x + 5 \]

So, the equation of line \( k \) is:

\[ y = -3x + 5 \]

Step 3: Determine the equation of line \( j \)

Since we do not have specific information about line \( j \), we need either coordinates or defined characteristics of this line to formulate its equation. Therefore, to complete the answer we could represent line \( j \) with a general form, such as:

\[ y = mx + b \]

Where \( m \) represents the slope of line \( j \) and \( b \) the y-intercept.

Final System of Equations

Assuming line \( j \)'s equation is represented by \( y = mx + b \) for some slope \( m \) and y-intercept \( b \), the system of equations representing both lines would be:

\[ y = -3x + 5 \quad (\text{for line } k) \ y = mx + b \quad (\text{for line } j) \]

If you later obtain specific information about line \( j \), you can amend it accordingly. Without that, it remains a variable representation.