Write the linear equation that gives the rule for this table.

x y
–80 –88
21 13
33 25
88 80

Write your answer as an equation with y first, followed by an equals sign.

1 answer

To find the linear equation that fits the given points, we can first determine the slope (\(m\)) and y-intercept (\(b\)) of the line.

We can use the formula for the slope:

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

Let's take two points from the table, for instance, (21, 13) and (33, 25).

Using these points:

\[ m = \frac{25 - 13}{33 - 21} = \frac{12}{12} = 1 \]

Now we have a slope \(m = 1\). Next, we can use one of the points to find the y-intercept (\(b\)). We'll use the point (21, 13).

The equation of a line can be expressed as:

\[ y = mx + b \]

Substitute \(m = 1\) and the point (21, 13):

\[ 13 = 1(21) + b \]

This simplifies to:

\[ 13 = 21 + b \] \[ b = 13 - 21 \] \[ b = -8 \]

Now we can write the equation of the line:

\[ y = 1x - 8 \]

This can be simplified to:

\[ y = x - 8 \]

Thus, the equation that gives the rule for the table is:

\[ y = x - 8 \]