Do Now 5/16/11 Copy HW in your planner. Copy HW in your planner. Text p. 467, #8-30 evens, & 19 Text p. 467, #8-30 evens, & 19 Be ready to copy POTW #6. Be ready to copy POTW #6.

In your notebook, list as many types of triangles that you can. Then draw a picture for each one.

Objective SWBAT classify triangles by their angles SWBAT classify triangles by their angles SWBAT use the Pythagorean Theorem to find the lengths of the sides of a right triangle SWBAT use the Pythagorean Theorem to find the lengths of the sides of a right triangle

Triangles can be classified by their SIDES and ANGLES. Triangles can be classified by their SIDES and ANGLES. a° c° b° C A B b a c Triangle Review

Classifying Triangles by their SIDES EQUILATERAL TRIANGLE – has 3 sides of the same length. ISOSCELES TRIANGLE – has at least 2 sides of the same length. SCALENE TRIANGLE – has 3 sides of DIFFERENT lengths.

Classifying Triangles by their ANGLES ACUTE TRIANGLE – has 3 acute angles. RIGHT TRIANGLE – has 1 right angle. OBTUSE TRIANGLE – has 1 obtuse angle.

Name the TRIANGLE ACUTEorEQUIANGULAR EQUILATERAL E D F ° 4

Name the TRIANGLE OBTUSE ISOSCELES 40° 100° 40° C A B

Name the TRIANGLE ACUTE SCALENE 46° 89° 45° C A B

Name the TRIANGLE RIGHT SCALENE

ACUTE EQUILATERAL

a c b hypotenuse (always across from the right angle (always across from the right angle and always the longest side ). and always the longest side ). legs right angle (90°) (90°) Section 9.3 “The Pythagorean Theorem”

The Pythagorean Theorem For any RIGHT TRIANGLE, the sum of the squares of the lengths of the legs, a a a a and b, equals the square of the length of the hypotenuse, c. a b c

Solving a Right Triangle In the triangle below, a = 6 and b = 7. Use the Pythagorean Theorem to find the length of the hypotenuse. In the triangle below, a = 6 and b = 7. Use the Pythagorean Theorem to find the length of the hypotenuse. a b c

Solving a Right Triangle In the triangle below, c = 10 and a = 6. Use the Pythagorean Theorem to find the length of the other leg. In the triangle below, c = 10 and a = 6. Use the Pythagorean Theorem to find the length of the other leg. a b c

Solving a Right Triangle In the triangle below, d and e are both 5. Use the Pythagorean Theorem to find the length of the hypotenuse. In the triangle below, d and e are both 5. Use the Pythagorean Theorem to find the length of the hypotenuse. de f The triangle is an The triangle is an ISOSCELES triangle- ISOSCELES triangle- the legs are the same length the legs are the same length

To Be or Not To Be… A Right Triangle Side lengths : 1, 2, 3 Side lengths : 3, 4, 5 Side lengths : 5, 12, 13

Your cat is at the top of a 15 foot tree. The bottom of the ladder that you will use will be placed 9 feet from the base of the tree. Can you reach the cat if the ladder is 20 feet in length? 9 feet 15 feet

Homework Text p. 467, #8-30 evens, & 19 Text p. 467, #8-30 evens, & 19