Boards Concepts Booster Class 9 Triangles

1. BOARDS CONCEPTS BOOSTER TRIANGLES  Download Doubtnut Today Ques No. Question CONCEPT FOR BOARDS || Chapter TRIANGLES 1. INTRODUCTION 1 1. What is triangle?  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 1. INTRODUCTION 2 2. Sides and Angles of triangle  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 1. INTRODUCTION 3 3. Types of triangle on the basis of Side  Click to LEARN this concept/topic on Doubtnut

2. CONCEPT FOR BOARDS || Chapter TRIANGLES 1. INTRODUCTION 4 4. Types of triangle on the basis of angles  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 2. PROPERTIES OF A TRIANGLE 5 1. The sum of the three angles of a triangle is 180∘  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 2. PROPERTIES OF A TRIANGLE 2. If two parallel lines intersected by a transversal; prove that the bisectors of the two pairs of interior angle encloses a rectangle. 6  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 2. PROPERTIES OF A TRIANGLE 3. The sum of two angles of a triangle is equal to its third angle. Determine the measure of third angle. 7  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES

3. 2. PROPERTIES OF A TRIANGLE 8 4. In a ; if ; Determine ΔABC 2∠A = 3∠B = 6∠C ∠A; ∠B and ∠C  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 2. PROPERTIES OF A TRIANGLE 5. A triangle ABC is right angled at A. AL is drawn perpendicular to BC. Prove that ∠BAL = ∠ACB 9  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 2. PROPERTIES OF A TRIANGLE 6. In ΔABC;∠B = 45∘; 10 ∠C = 55∘ and bisector of meets BC at a point D. find ∠A ∠ADB and ∠ADC  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 3. EXTERIOR ANGLE OF A TRIANGLE 1. Exterior angle theorem : If a side of a triangle is produced; the exterior angle so formed is equal to the sum of the two interior opposite angles. 11  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 3. EXTERIOR ANGLE OF A TRIANGLE Δ

4. 2. The sides AB and AC of a bisectors of ∠PBC are produced to P and Q respectively. If the meet at O ; Then ∠QCB ΔABC and 1 12 ∠BOC = 90∘− 2 ∠A  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 3. EXTERIOR ANGLE OF A TRIANGLE 3. The sides BC;CA and AB of a angles ∠ACD; ∠BAE and ; are produced in order; forming exterior ΔABC 13 . Show that ∠CBF ∠ACD + ∠BAE + ∠CBF = 360∘  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 4. CONGRUENCE 14 1. Congruence of Line segments  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 4. CONGRUENCE 15 2. Congruence of Angles  Click to LEARN this concept/topic on Doubtnut

5. CONCEPT FOR BOARDS || Chapter TRIANGLES 4. CONGRUENCE 16 3. Congruence of Triangles  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 4. CONGRUENCE 17 4. Congruence relation  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 7. SUFFICIENT CONDITION FOR CONGRUENCE OF TRIANGLE 2. Side Angle Side (SAS) Congruence - Two triangles are congruent if two sides and the included angle of one are equal to the corresponding sides and the included angle of the other triangle. 18  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 7. SUFFICIENT CONDITION FOR CONGRUENCE OF TRIANGLE 19 3. Angles opposite to two equal sides of a triangle are equal.  Click to LEARN this concept/topic on Doubtnut

6. CONCEPT FOR BOARDS || Chapter TRIANGLES 7. SUFFICIENT CONDITION FOR CONGRUENCE OF TRIANGLE 5. Angle-Side-Angle (ASA) Congruence - Two triangles are congruent if two angles and the included side of one triangle are equal to the corresponding two angles and the included side of the other triangle. 20  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 7. SUFFICIENT CONDITION FOR CONGRUENCE OF TRIANGLE 6. Angle Angle Side (AAS) Congruence - If any two angles and a non-included side of one triangle are equal to the corresponding angles and side of another triangle; the two ttriangles are congruent. 21  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 7. SUFFICIENT CONDITION FOR CONGRUENCE OF TRIANGLE 22 7. If two angles of a triangle are equal;then sides opposite to them are also equal.  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 7. SUFFICIENT CONDITION FOR CONGRUENCE OF TRIANGLE 8. If the altitude from one vertex of a triangle bisects the opposite side; then the triangle is isosceles. 23  Click to LEARN this concept/topic on Doubtnut

7. CONCEPT FOR BOARDS || Chapter TRIANGLES 7. SUFFICIENT CONDITION FOR CONGRUENCE OF TRIANGLE 24 9. In an Isoceless triangle altitude from the vertex bisects the base.  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 7. SUFFICIENT CONDITION FOR CONGRUENCE OF TRIANGLE 10. If the bisector of the vertical angle of a triangle bisects the base of the triangle;then the triangle is isosceles. 25  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 7. SUFFICIENT CONDITION FOR CONGRUENCE OF TRIANGLE 11. Side Side Side(SSS) Congruence : Two triangles are congruent if the three sides of one triangle are equal to the corresponding three sides of the other triangle. 26  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 7. SUFFICIENT CONDITION FOR CONGRUENCE OF TRIANGLE 14. Right Hand Side Congruence Condition(RHS) - Two right triangles are congruent if the hypotenuse and one side of one triangle are respectively equal to the hypotenuse and side of the other triangle. 27  Click to LEARN this concept/topic on Doubtnut

8. CONCEPT FOR BOARDS || Chapter TRIANGLES 8. SOME INEQUALITY RELATION IN A TRIANGLE 28 1. If two sides of a triangle are unequal; the longer side has greater angle opposite to it.  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 8. SOME INEQUALITY RELATION IN A TRIANGLE 29 2. In a triangle the greater angle has the longer side opposite to it.  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 8. SOME INEQUALITY RELATION IN A TRIANGLE 30 3. The sum of any two sides of a triangle is greater than third side.  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 8. SOME INEQUALITY RELATION IN A TRIANGLE 4. All the line segment that can be drawn to a given line; from a point;not lying on it; the perpendicular line segment is the shortest. 31  Click to LEARN this concept/topic on Doubtnut CONCEPT FOR BOARDS || Chapter TRIANGLES 8. SOME INEQUALITY RELATION IN A TRIANGLE 32 5. Distance Between A line and a points

9.  Click to LEARN this concept/topic on Doubtnut  Download Doubtnut to Ask Any Math Question By just a click  Get A Video Solution For Free in Seconds  Doubtnut Has More Than 1 Lakh Video Solutions  Free Video Solutions of NCERT, RD Sharma, RS Aggarwal, Cengage (G.Tewani), Resonance DPP, Allen, Bansal, FIITJEE, Akash, Narayana, VidyaMandir  Download Doubtnut Today