X | Y
-2 | 80
-1 | 70
2 | 40
5 | 10
Answer the questions using the table.
(3 points)
The rate of change = ____
The y-intercept = ____
The equation of the line is = ____
The rate of change = the change in y divided by the change in x
-2 | 80
-1 | 70
Change in y = 70 - 80 = -10
Change in x = -1 - (-2) = -1 + 2 = 1
Rate of change = -10/1 = -10
The y-intercept = the value of y when x = 0
From the given table, there is no data for x = 0, so we cannot determine the y-intercept.
The equation of the line can be found using the point-slope form:
y - y1 = m(x - x1)
Choosing the point (-2, 80) as (x1, y1), we have:
y - 80 = -10(x - (-2))
y - 80 = -10(x + 2)
y - 80 = -10x - 20
y = -10x + 60
So the equation of the line is y = -10x + 60.