1. The Pythagorean Theorem
Right Triangles ONLY

2. Remember the formula? c a
Legs
Hypotenuse b

3. 1. Finding the hypotenuse
a2 + b2 = c2
= c2
= c2
625 = c2 20 15 x

4. 2. Finding a side
a2 + b2 = c2
62 + b2 = 102
36 + b2 = 100
b2 = 64
b = 8 10 6 x

5. 3. See if the triangle is a right triangle5 4
a2 + b2 = c2
= 52
= 25
25 = 25 3
Yes we have a right triangle.

6. The ladder reaches 14 feet up the wall.
4. A 15 foot ladder leans up against a building. the foot of the ladder is 5 feet from the base of the building. How high up the wall, to the nearest foot does the ladder reach?
a2 + b2 = c2
x = 152
x =
x2 = 200
X = √200
x = 10√2 x 15 5
The ladder reaches 14 feet up the wall.

7. Tim is 9 miles from where he started.
Tim rode 8 miles due north, then 3 miles due east. How far, to the nearest mile, is Tim from where he started? 3
a2 + b2 = c2
= c2
= c2
73 = c2
√73 = C =c 8 x
Tim is 9 miles from where he started.

8. Remember the properties of a rhombus:
The diagonals of a rhombus are 6 cm and 8 cm. What is the length of each side of the rhombus?
Remember the properties of a rhombus:
The diagonals of a rhombus bisect each other
The diagonals of a rhombus are perpendicular
The sides of a rhombus are congruent

9. 3 4
a2 + b2 = c2
= c2
= c2
25 = c2
√25 = c
5 = c x 4 3
A rhombus is really 4 right triangles in disguise!
Each side of the rhombus measures 5 cm.

10. Need more help? Watch these videos