<em>First we must find out the slope of the points </em>
The equation for slope is
Let's plug in our points
Our slope is 0
When lines are parallel, that means we have they have the same slope
So a line that is parallel to <u>r</u> would have a slope of <u>0!</u>
You would make the proportion
24 / 6 = x/9, solve for x
How to find "a"???
Pick a point on the graph other than the vertex. Let's say you see the line pass through (1,5) and the vertex is at (3,4)...
First the vertex gives you this...
y = a (x - 3)2 + 4
Put the values (1,5) into this equation.
5 = a (1 - 3)2 + 4
Solve for a
5 = a*(-2)2 + 4
5 = 4a + 4
1 = 4a
1/4 = a
Final equation is
y = 1/4*(x - 3)2 + 4