Question

How do you find the value of k so that the slope of the line through the points (4 , 2) and (k , 6) is equal to -2?

Answer 1

The answer is: `k=2`.

Given two point, `A(x_a,y_a)` and `B(x_b,y_b)`the slope of the line that passes from them is:

`m=(y_b-y_a)/(x_b-x_a)`.

So:

`-2=(6-2)/(k-4)rArr-2(k-4)=4rArr`

`-2k+8=4rArr-2k=-4rArrk=2`.