Self-Assessment Solutions

Distance Between Points

1.	b = 18
2.	No
3.	130
4.
5.	(90,105)
6.	(60,85,25)

Parabolas

1.	(4,7)
2.	(1,5)
3.	( “3,2)
4.	( “12,0)
5.	( “1,0)

6.	The answer is shown in Figure 2.17. Figure 2.17. y = 10(x “1) 2 + 3.
7.	The answer is shown in Figure 2.18. Figure 2.18. x = y 2 “2.

Circles and Spheres

1.	center = (30,10), radius = 20
2.	center = ( “20,90), radius = 10
3.	center = ( “50,0), radius = 25

4.	( x “40) 2 + ( y +25) 2 = 900
5.	x 2 + y 2 = 225
6.	( x +10) 2 + ( y “40) 2 = 1000

7.	center = (10,30,50), radius = 40
8.	center = (0,0,0), radius = 10
9.	center = (50,0, “40), radius = 1

10.	( x “40) 2 + ( y +25) 2 + ( z “30) 2 = 100
11.	x 2 + y 2 + z 2 = 484
12.	( x “10) 2 + y 2 + ( z +60) 2 = 3400

Applications in Collision Detection

1.	Yes
2.	No
3.	Set up a hierarchy of spheres, and check the smaller ones only if the larger spheres have collided.