I do believe that the LCD of those would be 3
Think about rise over run. Make the -4 a fraction into -4/1. Rise is the first, so you go down 4 pts down. Then run is 1, so you go 1 right. In this case, there is no beginning, so you begin at 0. The coordinates will be (0, 0) and (1, -4). You got the graph.
Answer:
All of the degrees add up to 90. Therefore, right angle.
Answer: Choice A
The formula for the volume of a cone is 1/3 the volume of a cylinder. The volume of a sphere is 4/3 the volume of a cylinder, where the height of the cylinder is the same as the radius of the sphere
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Explanation:
As the first screenshot shows, the volume of a cone is 1/3 the volume of a sphere. The radius of each are the same. The height of each are the same as well.
The first screenshot also mentions "The volume of the half sphere is 2/3 the volume of the cylinder". The diagram shows the height of the cylinder (h) is equal to the radius of the half sphere. Based on this, the volume of a full sphere of radius r will be 4/3 times the volume of the cylinder with the same radius and height of 2r. You can think of having a spherical tennis ball inside a cylindrical can.
The first screenshot shows this when your teacher computed
to get 
Note how 
The stuff in parenthesis represents the volume of a cylinder with radius r and height h = r. This is one way to see that
SphereVolume = (4/3)*(CylinderVolume)
where the height of the cylinder is as discussed above.
ok so you need to take the 4x + 6y - 4 and make it (4*2 )+ (6*-4)- 4. Now solve is and it equals -20. So, your answer is -20.
Hope this was helpful!