When a line passes through the two points
, its slope is given by the formula 
In this question, a line L passes through the points 
So, its slope is given by

When two lines are perpendicular, then the product of their slopes is -1.
Since, the slope of the line L is
, so the slope of the line which is perpendicular to the given line L is
as the product of
.
In order to see the formulas that you used in a spreadsheet, but doesn't want to see the results of the formulas, then just click on Show Formulas. That can be done by clicking the cell and click, show formula. Letter A.
I’m not sure but i think it is 126 pi IM SORRY IF IM WRONGGGGG
What do u want help with and take it easy btw