Q15 of 169 Page 656

If the points A(a, 0), B(0, b) and P(x, y) are collinear, using slopes, prove that

Given points are A(a,0),B(0,b) and P(x,y)

For three points to be collinear, the slope of all pairs must be equal, that is the slope of AB = slope of BP = slope of PA.



Slope of AB =


Slope of BP =


Slope of PA =


Now Slope of AB = BP = PA



Using the first two equality





Dividing the equation by “ab”, We get




Hence proved.


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