Answer:
Point slope form: -9 = m(3)
Slope intercept form: y = -3x + 30
At x = 0, his delivery time was 30 minutes. It decreased by 3 minutes per day.
Step-by-step explanation:
We have 2 points to calculate the line.
(3, 21) x1 y1
(6, 12) x2 y2
First, we need to calculate the slope.
m =
m =
m = -3
Point slope form is:
y - y1 = m(x - x1)
So for our case:
-9 = m(3)
And slope intercept form is:
y = mx + b
We need to solve for the y intercept (b)
y = -3x + b --- enter the slope
21 = -3(3) + b --- enter in any point on the line for x and y
21 = -9 + b
b = 30 --- solve for b
Now our slope intercept form of the line is:
y = -3x + 30
At x = 0, his delivery time was 30 minutes. It decreased by 3 minutes per day.
