Geometry: An Interactive Journey to Mastery

Squaring and simplifying produces the following.

2 22

22 2

2

2

(^1144)
21611216
(^22).
xy y
xyyyy
x yy
xy

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This parabola is indeed the graph of y = x^2.
Study Tip
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study tips for this lesson other than to enjoy the lesson.
Pitfall
x Don’t forget to keep the geometry of conics in mind if you later study conics in an algebra course.

1. A stick of butter is the shape of a rectangular prism
   with a square cross section.
   If we cut the stick with a vertical cut parallel to a
   square face, the cross section obtained is a square,
   as shown in Figure 29.8.
   If we tilt the plane, we obtain a rectangle, as shown
   in Figure 29.9.

Problems

square

Figure 29.8

rectangleFigure 29.9