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If O is a point inside a triangleABC, pr...

If O is a point inside a `triangleABC`, prove that
`angleBOC=angleBAC+angleABO+angleACO`.

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MODERN PUBLICATION-LINES AND ANGLES-EXERCISE
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  2. In fig. if BP||CQ and AC=BC, then the measure of x is

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  3. In figure if AB||CD||EF,PQ||RS, angleRQD=25^@ and angleCQP=60^@ then a...

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  4. Prove that if one angle of a triangle is equal to the sum of the other...

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  5. An exterior angle of a triangle is less than either of its interior op...

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  6. The angles of a triangle are in the ratio 5:3:7. the triangle is

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  7. If one of the angles of a triangles is 130^@, then the angle between t...

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  8. In the given figure POQ is a line. The value of x is

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  9. Angles of a triangle are in the ratio 2:4:1 smallest angle of the tria...

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  10. In fig. PQ||ST=110^@, and angleRST=130^@, find angleQRS

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  11. Which type of angle has measure greater than 180^@ but less than 360^@...

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  12. In the fig. find x and y if x-y=70^@

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  13. In triangleABC, if angleA=12, angleB=15, angleC find all the angles of...

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  14. Two lines are respectively perpendicular to two parallel lines. Show t...

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  15. A triangle ABC is right angled at A. AM is drawn perpendicular to BC. ...

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  16. In the fig. bisectors AP and BQ of the alternate interior angles and p...

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  17. If O is a point inside a triangleABC, prove that angleBOC=angleBAC+ang...

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  18. A triangle can have two acute angles.

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  19. Prove that through a given point, we can draw only perpendicular to a ...

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  20. In the fig. angleQ>angleR, PA is the bisector of angleQPR and PMbotQR....

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