Transcript Chapter 8.2 Geometry

8.2 Special Right Triangles
Theorem 8.5 45-45-90 Triangle
Theorem
• In a 45-45-90 triangle, both legs are congruent
and the length of the hypotenuse is 2 time
the length of a leg.
45
• Hypotenuse=
2
x leg
s 2
s
45
90
s
Example #1
• Find the vale of each variable
90
45
9
45
x
Practice #1
• Find the value of each variable
y
45
2 2
45
90
Theorem 8.6 30-60-90 Triangle
Theorem
• In a 30-60-90 triangle, the length of the
hypotenuse is twice the length of the shorter
leg. The length of the longer leg is 3 times the
length of the shorter leg.
30
• Hypotenuse= 2 x shorter leg 2 s
• Longer leg= 3 x shorter leg
s 3
90
60
s
Proof of 30-60-90
60
2s
2s
60
60
2s
Example
• Find the value of the variable
30
5
f
60
90
d
Classwork/Homework
• Pgs 428-429 #1-8, 15, 21, 22
• Pgs 428-429 #9-14,16-20