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In a A B C , if /A=120^0a n d\ A B=A Cd...

In a ` A B C ,` if `/_A=120^0a n d\ A B=A Cdot` Find `/_B\ a n d\ /_C`

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Given: `AB=AC`
`=>∠B=∠C` [Angles opposite to equal sides are equal]
Sum of angles in a triangle`=180°`
`∠A+∠B+∠C=180°`
`=>∠A+∠B+∠B=180°`
`=>120°+2∠B=180°`
`2∠B=180°-120° =60°`
`=>∠B=30°`
`therefore ∠B=∠C=30°`
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RD SHARMA-CONGRUENT TRIANGLE -All Questions
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  2. Prove that the medians of an equilateral triangle are equal.

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  3. In a A B C , if /A=120^0a n d\ A B=A Cdot Find /B\ a n d\ /C

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  4. In A B C , if A B=A C\ a n d\ /B=70^0, find /A

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  5. The vertical angle of an isosceles triangle is 100^0dot Find its bas...

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  6. In Figure, AB=AC and /A C D=10^@, find /BAC

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  7. Find the measure of each exterior angle of an equilateral triangle.

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  8. If the base of an isosceles triangle is produced on both sides, prov...

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  9. In Figure, AB=AC and DB=DC , find the ratio /A B D\ :\ /A C D

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  10. Determine the measure of each of the equal angles of a right-angled ...

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  11. A B C is a right-angled triangle is which /A=90^0a n d\ A B=A Cdot F...

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  12. A B is a line segment. P\ a n d\ Q are points on opposite sides of A...

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  13. In Figure, diagonal A C of a quadrilateral A B C D bisects the angles ...

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  14. A B is a line segment. A X\ a n d\ B Y are two equal line segments d...

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  15. l\ a n d\ m are two parallel lines intersected by another pair of pa...

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  16. In Figure, if A B||D C\ a n d\ P is the mid-point B D , prove that P i...

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  17. In Figure, /B C D=/A D C\ a n d\ /A C B=/B D Adot Prove that A D=B C\ ...

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

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  19. In Figure, A C=B C ,\ /D C A=/E C B\ a n d\ /D B C=E A Cdot Prove that...

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