y = |x + k| - 2
"has an x-intercept of 4." means that the graph passes through
the point (4,0), Since 4 is the x-coordinate and 0 is the
y-coordinate, substitute x=4 and y=0
0 = |4 + k| - 2
Add 2 to both sides
2 = |4 + k|
Break into two equations:
4 + k = 2 and 4 + k = -2
k = -2 k = -6
So the two values of k means that there are two
answers:
y = |x - 2| - 2 and y = |x - 6| - 2
Here are the two graphs:
Notice that they both go through the point (4,0) on the
x axis. They both intercept the x-axis there.
Edwin