Question

The line of best fit for a scatter plot is shown:

Answer 1

In the slope intercept form, b represents the y intercept.
y = mx +- b

Therefore, if the y intercept is at 6, the formula of the line will look like
y=mx + 6

This eliminates the first two options, 
$y = -6x + \frac{3}{4}$
and
$y=6x + \frac{3}{4}$

and leaves behind
$y= - \frac{3}{4} +6$
and
$y= \frac{3}{4} x+6$

Since the line you indicated is sloping downwards towards the lower right hand corner. It must have a negative slope.

Therefore, the answer must be the 3rd option.

$y= - \frac{3}{4} +6$