# Given a circle: C(1,2) & radius #sqrt(5)# a) Find the perpendicular distance from center to #x + 2y -10=0#, show this line is a tangent to the circle. b) Find the perpendicular distance from center to #x+2y -12 =0#, show the line does not meet circle?

##### 1 Answer

Nov 14, 2016

The distance of C to the first line is exactly

#### Explanation:

The general formula for the distance of the generis point

so the distances are