Question 1005462
the two lines y=6x+15 and y=mx-4 intersect at x=-2. What is the y coordinate of their intersection point.....and what is the value of m?
-------
Wherever the equations intersect their y values are the same, 
and their x values are the same.
----
Since the y values are the same,
Solve:: 6x+15 = mx-4
Since x = -2 when the lines intersect, 6*-2+15 = m(-2)-4
-2m -4 = -12+15
-2m = 3+4
m = -7/2
----
Find the y coordinate of the intersection point::
Since y = 6x+15
Solve:: y = 6(-2)+15 = -12+15 = 3
----------------
Cheers,
Stan H.
------------





-----------------------
For the equation y