Page 115 - NUMINO Challenge_C1

13 Unit Area

Basic Concepts Unit Area

The area of each figure below can be found using the shaded unit.

11

1

Area 6 Area 8 Area 9

The area of a figure can be measured by dividing it into the smallest possible
unit. We call the area of this unit the unit area.

Example When equilateral triangle ABC has an area of 100, A
what is the area of equilateral triangle DEF ? D

E F
B C

Class Notes

If you rotate triangle DEF 60 clockwise, the area of triangle ABC becomes times
the area of triangle DEF.

A A
D ED
B FC
E F
B C

Since the area of triangle ABC is 100, the area of triangle DEF is
100 .

Try It Again When square EFGH has an area of 80, what A D
is the area of square ABCD? E H
G
F
B C

112 NUMINO Challenge C1