Transcript 8.2 Special Right Triangles - Cardinal O'Hara High School

8.2 Special Right Triangles
• Certain right triangles have properties that allow
you to use shortcuts to determine side lengths
without using the Pythagorean Theorem.
• 45° - 45° - 90° Triangles
• 30° - 60° - 90° Triangles
45°- 45°- 90°
• In a 45° - 45° - 90° triangle, both legs are
congruent and the length of the hypotenuse is
the square root of 2 times the length of the leg.
Finding the Length of the Hypotenuse
• What is the value of each variable?
h  9 2
h9 2
h2 2 2
h2 4
h  22
h4
Finding the Leg
• What is the value of x?
6  x 2
6
x
2
6
2
x

2 2
6 2
x
2
x3 2
30° - 60° - 90°
Using the Length of One Side
• What is the value of d in simplest radical form?
5d 3
5
d
3
5
3
d

3 3
5 3
d
3
More Practice!!!!!
• Homework – Textbook p. 503 – 504 #7 –
12, 15 – 20 ALL.