1. Week 11 day 5
OZ is a bisector of / XOY. Which of the following statements
is NOT true? A
2m<ZOY = m<XOY
2m<XOZ = m<XOY B C
m<XOY = m<XOZ D
m<ZOY = ½ m<XOY 2

2. 8.1 The Pythagorean Theorem and Its Converse

3. Pythagorean Theorem
In a right triangle, the sum of the squares of the lengths of the legs is equal to the square of the length of the hypotenuse. a b c
a2+b2 = c2

4. Converse of the Pythagorean Theorem
If the square of the length of one side of a triangle is equal to the sum of the square of the lengths of the other two sides, then the triangle is a right triangle.
TRIANGLE CHECK! a b c
c2 = a2 + b2

5. Here are some other theorems
If the square of the length of the longest side of a triangle is greater than the sum of the squares of the lengths of the other sides, the triangle is obtuse. a b c
a2 + b2 < c2

6. Here are some other theorems
If the square of the length of the longest side of a triangle is less than the sum of the squares of the lengths of the other sides, the triangle is acute. a b c
a2 + b2 > c2

7. 42+52=62 16+25=36 41>36 acute triangle
What kind of triangle has the following sides? ?
42+52=62 ?
16+25=36
4, 5, 6
41>36
acute triangle

8. Lets try a problem
x2+162=202
x2+256=400 x 20 16
x2=144
x=12

9. Workbook p. 397 all

10. Assignment
Workbook
Page 397 all