Page 64 - NUMINO Challenge_D1
P. 64
Basic Concepts Transparent Cubes
The following shows the front and top views of a transparent cube after a
red line has been drawn on the cube.
Front View Top View
By looking at just the front view, the exact location of the red line is not
known. However, if you look at the top view as well, you will see that the red
line is drawn on the back face of the cube.
The location of the line is not known by looking from just one direction.
Therefore, you must look at the cube from different directions.
Example In a transparent cube with edges of 8 cm, a rectangle is colored on
the front face, and a triangle is colored on the back face. If you are
looking at the front view of the cube, find the area of the colored
part.
Back
Class Notes Front Colored part on the Colored part on the
front face back face
The area of the rectangle on the front face is cm2.
The area of the triangle on the back face is cm2.
Draw the colored part of the front view: . The area is cm2.
Try It Again The front and back faces of a transparent cube are colored as
shown below. If you are looking at the front view of the cube,
what is the fraction of the colored part compared to one face
of the cube?
Back
Front Colored part on the Colored part on the
front face back face
61Geometry
The following shows the front and top views of a transparent cube after a
red line has been drawn on the cube.
Front View Top View
By looking at just the front view, the exact location of the red line is not
known. However, if you look at the top view as well, you will see that the red
line is drawn on the back face of the cube.
The location of the line is not known by looking from just one direction.
Therefore, you must look at the cube from different directions.
Example In a transparent cube with edges of 8 cm, a rectangle is colored on
the front face, and a triangle is colored on the back face. If you are
looking at the front view of the cube, find the area of the colored
part.
Back
Class Notes Front Colored part on the Colored part on the
front face back face
The area of the rectangle on the front face is cm2.
The area of the triangle on the back face is cm2.
Draw the colored part of the front view: . The area is cm2.
Try It Again The front and back faces of a transparent cube are colored as
shown below. If you are looking at the front view of the cube,
what is the fraction of the colored part compared to one face
of the cube?
Back
Front Colored part on the Colored part on the
front face back face
61Geometry
