You can
put this solution on YOUR website!
add 8 to both sides
divide both sides by 2
I can see that
and
This problem can only be understood by plotting it.
plot
by plotting
and
The plot goes up and to the right with slope = +1, bounces off the u-axis
at (-3,0), then goes up and to the left with slope = -1, but
everything below the horizontal line y = 2 must be excluded because
. In summary, u can have ANY value except those
between u = -1 and u = -5.
Note that, even though (-3,0) is not a valid point, u = -3 is
the axis of symmetry for the solution.
You can test this
Let u = +10
then y will be 13
If -3 is the axis of symmetry, y should have the same value on the
other side of u = -3
10 - (-3) = 13
-u - (-3) = 13
-u = 16
u = -16
The right side shows that u = -3 is an axis of symmetry
