You can identify the lines and their colour either by
1. the y-intercepts.
First equation has a y-intercept of 3 and second has a y-intercept of 2.
So first equation is blue, and second is red.
2. the slopes
First equation has a negative slope (so blue), and second has a positive slope (so red).
Now work on each of the equations.
1. first equation (blue)
If we put x=0, we end up with the equation y≤3, the ≤ sign indicates that the region is BELOW the BLUE line.
2. second equation (red).
If we put x=0, we end up with the equation y>2, the > sign indicates that the region is ABOVE the RED line AND the red line should be dotted (full line if ≥).
So at the point, it won't be too hard to find the correct region.
To confirm, take a point definitely in the region, such as (-6,0) and substitute in each equation to make sure that both conditions are satisfied.

By the fundamental theorem of calculus,

Now the arc length over an arbitrary interval

is

But before we compute the integral, first we need to make sure the integrand exists over it.

is undefined if

, so we assume

and for convenience that

. Then
<span>I just worked out the problem , the answer should be ....
2,304 π cubic units
Hope this helps.</span>