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(Exterior Angle Theorem): If a side of a...

(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. GIVEN : A triangle `A B C,D` is a point of `B C` produced, forming exterior angle `/_4.` TO PROVE : `/_4=/_1+/_2` i.e. , `/_A C D=/_C A B+/_C B Adot`

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`In /_ABC`
`/_1+/_2+/_3=180^@-(1)`
`/_3+/_4=180^@-(2)`
from equation 1 and 2
`/_1+/_2+/_3=/_3+/_4`
`/_1+/_2=/_4`
`/_CAB+/_CBA=/_ACD`.
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RD SHARMA ENGLISH-CONGRUENT TRIANGLE -All Questions
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  2. l and m are two parallel lines intersected by another pair of parall...

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  3. (Exterior Angle Theorem): If a side of a triangle is produced, the e...

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  4. Two triangles are congruent if include two angles and the included s...

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  5. A ,B ,C are three angles of a triangle. If A-B=15^0,B-C=30^0, find /A...

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  6. In the figure, diagonal A C of a quadrilateral A B C D bisects the ang...

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  7. In a triangle A B C ,/A B C=/A C B and the bisectors of /A B C and /...

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  8. In Figure, /B C D=/A D C and /A C B=/B D Adot Prove that A D=B C and /...

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  9. If each angle of a triangle is less than the sum of the other two, ...

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  10. In two right triangles, one side and an acute angle of one triangle...

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  11. If Figure, if Q T|P R ,/T Q R=40^0 AND /S P R=30^0, find x and ydot F...

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  12. If D is any point on the base B C produced, of an isosceles triangle A...

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  13. sides Q P and R Q of P Q R are produced to point S and T respectively....

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  14. Show that in a right triangle the hypotenuse is the longest side. GI...

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  15. An exterior angle of a triangle is 110^0 , and one of the interior opp...

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  16. Show that the sum of the three altitudes of a triangle is less than ...

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  17. The sides B C ,C A and A B of a triangle A B C , are produced in or...

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  18. Prove that any two sides of a triangle are together greater than twi...

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  19. Prove that the sum of the three angles of a triangle is 180^0dot

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  20. In a triangle A B C , if /A=50^0 and /B=60^0 , determine the shortest...

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