The sum of all the interior angles of a triangle.
What is 180o?
State the triangle inequality theorem.
What is "the sum of any two sides of a triangle must be greater than the third side"?
Combined, a 59 degree angle and a 31 degree angle are . . .
What is complementary?
Work: 59 + 31 = 90
Determine the missing angle.
What is 71o?
Work:
82 + 27 + x = 180
109 + x = 180
x = 180 - 109
x = 71
Determine if a triangle can be drawn with the sides 11, 12, and 17.
What is yes?
Work:
11 + 12 > 17
11 + 17 > 12
12 + 17 > 11
Identify the angle pair relationship.
What is supplementary?
Work: 146 + 34 = 180o
Determine the missing angle.
What is 49o?
Work:
90 + 41 + x = 180
131 + x = 180
x = 180 - 131
x = 49
Determine if a triangle can be drawn with the sides 4, 8, and 15.
What is no?
Work:
4 + 8 < 15
Identify the angle pair relationship and solve for x.
What is complementary, x = 53o
Work:
x + 37 = 90
x = 90 - 37
x = 53
Use the angle sum rule to determine the value of x.
What is x = 12o?
Work:
90 + 2x + 1 +5x + 5 = 180
96 + 7x = 180
7x = 84
x = 12
The missing side (x) must be at between ___ and ___ .
What is between 3 and 10?
Work: 3 + 8 = 11, but if x is bigger than 10 it will become the longest side .
(and the inequality wont work)
Identify the angle pair relationship and solve for x.
What is vertical angles, x = 49
Work:
126 = x + 77
126-77 = x
49 = x
Use the angle sum rule to determine the value of x.
What is x = 14?
Work:
7x - 11 + 2x - 3 + 5x - 2 = 180
14x - 16 = 180
14x = 196
x = 14
Identify which set of numbers could NOT make a triangle.
(a)6,8,11
(b)9,12,19
(c)7,11,18
(d)5,6,7
What is (c)?
Work: 7 + 11 = 18
This is not greater than the other side (18) so these numbers cannot form a triangle
Identify the angle pair relationship and find the measure of q.
What is supplementary, q = 22
Work:
(7q−46) + (3q+6) = 180
10q − 40 = 180
10q = 180 + 40
10q = 220
q = 22