Given:
Scatter plot of weight loss plan.
To find:
how many pounds were lost per month with 4 hours of weekly.
Solution:
Take any two points on the trend line.
Let the points are (3, 4) and (5, 7).
Slope of the line:
[tex]$m=\frac{y_2-y_1}{x_2-x_1}[/tex]
[tex]$m=\frac{7-4}{5-3}[/tex]
[tex]$m=\frac{3}{2}[/tex]
m = 1.5
Using point-slope formula:
[tex]y-y_1=m(x-x_1)[/tex]
[tex]y-4=1.5(x-3)[/tex]
[tex]y-4=1.5x-4.5[/tex]
Add 4 on both sides.
[tex]y=1.5x-0.5[/tex]
Approximate equation of a line is y = 1.5x - 0.5
Substitute x = 4.
y = 1.5(4) - 0.5
y = 6 - 0.5
y = 5.5
Which is nearly equal to 6.
Also see in the scatter plot, y-value for the corresponding value of 4 in x-axis is 6.
Hence 6 pounds lost per month with 4 hours of weekly aerobic activity.
