Find the radius of the smallest circle which touches the straight line 3x– y = 6 at (1, –3) and also touches the line y = x. complete up to one place of decimal.


Correct option is

r = 1.5

The two lines meet at B (3, 3) 








 Also from the figure,  










                        = 1.49 

                      r = 1.5. 



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