Download Triangles

Triangles
Triangles can be classified by it angles
O
O
 Acute triangle: all three angles are acute (0 -90 )
O
O
 Obtuse triangle: one of the angles is an obtuse angle (90 -180 )
O
 Right triangle: one of the angles is a right angle (90 )
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Hypotenuse is across fro the 90O angle
Sides are related by a2 + b2 = c2
o a and b are the legs and c is the hypotenuse
Equiangular triangle: all three angles are the same measure, 60O
Triangles can be classified by it sides:
 Scalene: all side are different lengths
 Isosceles Triangle: two sides are the same length
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Two congruent sides are called the legs
Third side is called the base
Base angles are congruent
Equilateral Triangle: all three sides are the same length
The measure of all interior angles of a triangle add up to 180O.
The measure of all exterior angles of a triangle add up to 360O.
Triangle ABC is an isosceles triangle. The measure of angle B is 30. What is the measure
of angle A.
a.
b.
c.
d.
e.
15O
30O
75O
60O
90O
Triangle ABC is an equilateral triangle. What is the measure of angle D?
a. 60O
b. 90O
c. 95O
d. 180O
e. 185O
Special Right Triangles:
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45O, 45O, 90O Right Triangle
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Both legs are congruent
Hypotenuse is 2 time the length of the leg
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Shorter leg is across from the 30O angle
Larger leg is across from 60O angle
 Large = 3 time the length of shorter leg
Hypotenuse is across from the 90O angle
 Hypotenuse = 2 times length of the shorter leg
30O, 60O, 90O
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You are laying square tiles on your floor. If one tile has a diagonal length of 16
centimeters, how long is each side to the nearest tenth of a centimeter?
a. 13.9 cm
b. 11.3 cm
c. 22.6 cm
d. 27.7 cm
Which of the following cannot be lengths of a sides of a 30O, 60O, 90O triangle?
a. 8, 4, 4 3
b. 6, 12, 12 3
7 7
3
c. 7, ,
2 2
d. 5, 2.5, 2.5 3
A garden has side lengths of 14 feet. How far is it from one corner of the garden to the
opposite corner?
a. 7 2 feet
b. 14 2 feet
7 2
c.
feet
2
d. 7 3 feet
If MNPQ is a rectangle, what is MP?
a. 6 3
b. 6 5
c. 6
d. 2 3