A line of best fit for a data set is defined by the equation y=−0.8x+2.5
.
Which is the residual, r
, for the point (8, −2.3)
in the data set?
CLEAR SUBMIT
r=−4.8
r=−3.9
r=0.2
r=1.6
The residual can be calculated by subtracting the predicted y-value (based on the line of best fit equation) from the actual y-value.
Using the equation y = -0.8x + 2.5, we substitute x = 8 to find the predicted y-value:
y = -0.8(8) + 2.5
y = -6.4 + 2.5
y = -3.9
The actual y-value for the point (8, -2.3) is -2.3.
Now we calculate the residual:
r = actual y-value - predicted y-value
r = -2.3 - (-3.9)
r = -2.3 + 3.9
r = 1.6
Therefore, the residual for the point (8, -2.3) in the data set is 1.6.