linear functions

To calculate the slope, we need the Delta Y over the Delta X. 

 

 

So, the delta Y is: -2 - r 

 

And the Delta X is: 3 - 5

 

We are left with:

\(\begin{array}{l}\frac{-2-r}{3-5}\ =\ -2\\ \\ =\ \frac{-2-r}{-2}=-2\\ =-2-r\ =\ 4\\ -r\ =\ 4\ +2\\ r\ =\ -6\\ \\ \\ \end{array}\)

 

Therefore the value of r = -6. 

 

Heres the proof

(5, -6) --> (3, -2)

 

m = -2 - (-6)  ÷  (3 - 5)

    = 4 / -2 = -2.

 

Therefore r = -2

 

 

 

(Solved by a 12 y/o - Yep! )