Answer:
6 different ways? because theres only 6 books left to put on the shelf
We are given the equations 3x+5y=-3 and x-5y=-5.
Both equations have a 5y term which allows us to easily solve the system by elimination. To do so we will add the equations together like a simple addition problem by adding the x terms together, the y terms together, and the integer answers together.
3x + 5y = -3
+x - 5y = -5
---------------
4x + 0y = -8
The y terms cancel out since one is positive and one is negative. Now we can solve for x.
4x = -8

x = -2
Now plug -2 in for x in one of the original equations to find y.
(-2) - 5y = -5
-5y = -3
y = 3/5
Our answer as an ordered pair is (2, 3/5)
Plug
into the equation of the ellipsoid:

Complete the square:

Then the intersection is such that


which resembles the equation of a circle, and suggests a parameterization is polar-like coordinates. Let



(Attached is a plot of the two surfaces and the intersection; red for the positive root
, blue for the negative)