SOLUTION: I need answer to this asap. I'm just not getting these... -4<=2(u+3)-8 The (u+8) is absolute value

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Question 42763: I need answer to this asap. I'm just not getting these...
-4<=2(u+3)-8
The (u+8) is absolute value

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
-4+%3C=+2%2Aabs%28u%2B3%29-+8+
add 8 to both sides
4+%3C=+2%2Aabs%28u%2B3%29
divide both sides by 2
2+%3C=+abs%28u%2B3%29
I can see that u+%3E=+-1 and u+%3C=+-5
This problem can only be understood by plotting it.
plot y+%3C=+abs%28u%2B3%29 by plotting
y+%3C=+u+%2B+3 and y+%3C=+-u+-+3
+graph%28+300%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C+x%2B3%2C+-x-3%29+
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
2+%3C=+abs%28u%2B3%29. 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
y+%3C=+abs%28u%2B3%29
%2B10+%3C=+abs%2810+%2B+3%29
%2B10+%3C=+abs%2813%29
%2B10+%3C=+abs%28-16+%2B+3%29
%2B10+%3C=+abs%28-13%29
The right side shows that u = -3 is an axis of symmetry