6th Grade Math Textbook, Progress

Triangles

10-8

Draw an example of each type of triangle on dot paper.

1. isosceles 2. acute 3.obtuse 4. scalene


2. right 6. equilateral 7. isosceles obtuse 8. scalene acute

Classify each triangle by the measure of its sides

and by the measure of its angles.

D E

F

Matching tick marks

indicate congruent sides.

65 ° 40 °

17 mm^75 °

27 mm

25 mm 60 °

60 ° 60 °

10 m

10 m 10 m 40 cm 40 cm

60 cm

106 °

37 ° 37 °

60 °

30 °

4 m

3 m

5 m

Triangles are classified by the lengths of their

sides and/or by the measures of their angles.

Sides

equilateral triangle (A)—all sides congruent

isosceles triangle (B)—two sides congruent

scalene triangle (C)—no sides congruent

Angles

acute triangle (D)—three acute angles

obtuse triangle (E)—one obtuse angle

right triangle (F)—one right angle

Triangles can also be classified by both the lengths of

their sides and by the measures of their angles.

Both Sides and Angles

isosceles right triangle (G)—two sides

congruent and one right angle

scalene obtuse triangle (H)—no sides

congruent and one obtuse angle

A

B C

G H

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