Question

The equation of the linear regression line represents the relationship between the number of cars washed for charity, x, and the amount earned for the charity, y. What does the slope of the line represent? y = 10x +20

For every car washed for charity, the amount earned for the charity increases by $2.

For every car washed for charity, the amount earned for the charity increases by $10.

For every car washed for charity, the amount earned for the charity increases by $1.

For every car washed for charity, the amount earned for the charity increases by $20.

Answer 1

y = 10x + 20

x = number of cars washed for charity
y = amount earned for the charity
slope = 10

This means that : 

For every car washed for charity, the amount earned for the charity increases by $10. 

Answer 2

Answer with explanation:

If the Equation of Regression line is,

y= a + bx

a = Y intercept

b = Slope of line, it can be positive, negative or zero.

1. If b is positive, for every increase in x by 1, y value increases by b unit.

2. If b is negative, that is if x increases by 1 unit, y value decreases by -b unit.

3. If b=0, that is for increase in x by 1 unit, y neither increases nor decreases.

→→Here, the given regression line is

  y = 10 x + 20,

where linear regression line represents the relationship between the number of cars washed for charity, x, and the amount earned for the charity, y.

Slope =10

Y -Intercept = 20

For, every increase in x by 1 unit , y value increases by 10 unit.

Option B: For every car washed for charity, the amount earned for the charity increases by $10.