In a plane there are 37 straight lines of which 13 pass through point A and 11 pass through the point B . Moreover, no three lines (apart from the lines passing through A and B ) pass through same point and no two are parallel. What is the

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In a plane there are 37 straight lines of which 13 pass through point A and 11 pass through the point B . Moreover, no three lines (apart from the lines passing through A and B ) pass through same point and no two are parallel. What is the number of points of intersection of the straight lines?

Quantrex Academy · Accepted Answer

Correct answer: C. ³⁷ C₂- ¹³ C₂- ¹¹ C₂+2

Number of selection of two lines = ³⁷ C₂ Number of selection of two lines from lines which are concurrent at point A= ¹³ C₂ Number of selection of two lines from lines which are concurrent at point B= ¹¹ C₂ Total number of points of intersection = ³⁷ C₂- ¹³ C₂- ¹¹ C₂+2

In a plane there are 37 straight lines of which 13 pass through point A and 11 pass through the point B . Moreover, no three lines (apart from the lines passing through A and B ) pass through same point and no two are parallel. What is the number of points of intersection of the straight lines?

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