here is how to do it:
Explanation:
(h,k) are the coordinates of the vertex. They correspond to (x,y). So, first, you need to plug the vertex coordinates in for h and k in the given formula. Then, to find the a value (slope) you need to plug in the “contains” value in for x and y accordingly. Finally, just solve for a by simplifying algebraically. Make sure to distribute the - sign to your h and k values.
When you have the a value, to write the equation, do the following:
1. make sure to leave the vertex coordinates in the given formula equation
2. take out the “contains” values for x and y.
3. leave in the a value you found
Your completed equation should have the same format as the given formula. However, it should have numbers for the h, k, and a values. The x and y values should stay x and y.