logging in or signing up MATHS PPT. charanjeetahluwalia Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: Embed: Flash iPad Copy Does not support media & animations WordPress Embed Customize Embed URL: Copy Thumbnail: Copy The presentation is successfully added In Your Favorites. Views: 6051 Category: Education License: All Rights Reserved Like it (7) Dislike it (3) Added: June 11, 2010 This Presentation is Public Favorites: 2 Presentation Description No description available. Comments Posting comment... By: pri_123 (34 month(s) ago) nicc one.... liked it vry much Saving..... Post Reply Close Saving..... Edit Comment Close By: dipakshi (34 month(s) ago) vry nice ppt Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Slide 1: MATHS PROJECT BY CLASS 7-B GROUP MEMBER NAMES JASMEEN KAUR AHLUWALIA SANYA GUPTA KARAN PAL SINGH CHAHAL RAADHIKKA SEHGAL RAGHAV KHANNA PROPERTIES OF TRIANGLES TRIANGLES : TRIANGLES A closed figure made up of 3 line segments is called a triangle. A triangle has three sides, three vertices and three angles. TYPES OF TRIANGLES : TYPES OF TRIANGLES On the basis of sides: Equilateral triangle. Scalene triangle. Isosceles triangle. On the basis of angles: Acute angled triangle. Obtuse angled triangle. Right triangle. Classification of triangles on the basis of angles. : Classification of triangles on the basis of angles. Acute angled triangle- A triangle each of whose angle measures less than 90 deg. is called an acute triangle. Right triangle- A triangle one of whose angles measure 90 deg. is called a right triangle. Obtuse triangle- A triangle one of whose angle measures more than 90 deg. is called an obtuse triangle. Classification of triangles on the basis of sides : Classification of triangles on the basis of sides Equilateral triangle- A triangle having all sides equal is called an equilateral triangle. Isosceles triangle- A triangle having two sides equal is called an isosceles triangle. Scalene triangle- A triangle having all sides of different lengths is called a scalene triangle. Angle sum property of a triangle : Angle sum property of a triangle In a triangle, the sum of 3 interior angles is 180 degrees. Triangle inequality : Triangle inequality The sum of any two sides of a triangle, is greater than the third side. Questions and answers : Questions and answers Q1. In a ΔABC, if angle A= 72° and Angle B= 63°, find the measure of angle C. Ans. Angle C +72°+ 63°=180° ( Angle sum property) Angle C + 135°= 180°. Angle C= 180°- 135° Angle C= 45° Q2. In a ΔPQR, if angle Q= 105° and angle R= 40°, find the measure of angle P. Ans. Angle P + 105°+40°=180°. ( Angle sum property). Angle P + 145°= 180°. Angle P= 180°- 145°. Angle P= 35°. Questions And Answers : Questions And Answers Q3. The two interior opposite angles of an exterior angle of a triangle are 60°and 80°. Find the measure of the exterior angle. Ans. Let the exterior angle be x. x= 60 +45 ( exterior angle property) x= 105°. Q4. An exterior angle of a triangle is of measure 70° and one of its interior opposite angles is of measure 25°. Find the measure of the other interior opposite angle. Ans. Let the other interior opposite angle be x. x= 70 – 25 x= 45°. Questions and answers : Questions and answers Q5. Two angles of a triangle are 30° and 80°. Find the measure of the third angle. Ans. Let the third side be x. x + 30°+ 80°= 180° x+ 110° = 180° x= 180°-110° x= 70°. Q6. One of the angles of a triangle is 80° and the other two angles are equal. Find the measure of the two angles. Let both the angles be x x+ x+ 80°= 180° (Angle sum property) 2x + 80°= 180°. 2x= 180°- 80°. 2x = 100°. x= 50°. General Questions : General Questions Q1. Solve this equation: 5t + 28= 10 5t= 10- 28 5t = -18 t = -18/5 Q2. Solve: -4(2+ x)=8 -4X2 + (-4)Xx=8 -8 + (-4)x= 8 -8-4x = 8 -4x = 8+8 -4x= 16 x= -4 General Questions : General Questions Q3. Solve: 3( n-5)= 21 3n-3X5= 21 3n- 15= 21 3n =21+15 3n= 36 n= 12. Q4.Solve: 4 (2-x)= 8 8- 4x= 8 -4x= 8-8 -4x= 0 Exterior angle property : Exterior angle property In a triangle the exterior angle is equal to the sum of interior opposite angles. You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.