Question

Shannon drew the line of best fit on the scatter plot shown below:

Answer 1

Using the points (0,14) and (10,0), the gradient of the line is (14-0)/(0-5) which simplifies to -7/5.

From these points, we can also see that when the x value is zero, the y value is 14. Therefore the y-intercept is 14.

We can then put this into the equation of a straight line, y=mx+c:

y = (-7/5)x + 14

Answer 2

Answer:

Option A.

Step-by-step explanation:

If a line passes through two points $(x_1,y_1)$ and $(x_2,y_2)$, then the equation of line is

$y-y_1=\frac{y_2-y_1}{x_2-x_1}(x-x_1)$

It is given that the line of best fit passes through the points (0,14) and (10,0).

Using the above formula the equation of best fit line is

$y-14=\frac{0-14}{10-0}(x-0)$

$y-14=\frac{-14}{10}(x)$

$y-14=-\frac{7}{5}(x)$

Add 14 on both sides.

$y-14+14=-\frac{7}{5}(x)+14$

$y=-\frac{7}{5}(x)+14$

The equation of best fit line is $y=-\frac{7}{5}(x)+14$.

Therefore, the correct option is A.