4-1 Classifying Triangles B Side Angle A C Vertex

Classified by Angles Acute Triangle: all angles are Acute Obtuse Triangle: 1 angle is Obtuse Right Triangle: 1 angle is Right (90°) Obtuse Triangle Right Triangle Acute Triangle

Equiangular Triangle An acute triangle with all angles congruent.

Classified by Sides Scalene Triangle: No sides are congruent Isosceles Triangle: 2 sides are congruent Equilateral Triangle: All 3 sides are congruent. Scalene Isosceles Equilateral

Classify each triangle by its Angles and Sides Right Scalene B Obtuse Isosceles

XY=ZX 2n + 2 = 10 2n = 8 n = 4 XY = 10 YZ = (2(4)) – 2 = 8 – 2 = 6 Find the measures of side XY and YZ of isosceles triangle XYZ if X is the vertex angle (the angle in between the two congruent sides). X XY=ZX 2n + 2 = 10 2n = 8 n = 4 XY = 10 YZ = (2(4)) – 2 = 8 – 2 = 6 2n + 2 10 Y Z 2n - 2

Use the distance formula to find the lengths of each side of the triangle. Remember the distance formula

Try These ~ page 205 #1-6 1. Obtuse 2. Equiangular 3. ABC 4. ACD 5. x = 11, LN = 29, MN = 29 6. x = 5, QR, RS, QS = 25