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If the lines 3x -4y + 4 = 0 and 6x- 8y-7 = 0 are tangents to a circle, then radius of the circle is

Answer:

Explanation:

The diameter of the circle is the perpendicular distance between the parallel lines (tangents) 3x-4y+ 4 = 0 and3x-4y-$\frac{7}{2}$ = 0

and so it is equal to $\frac{4}{\sqrt{9+16}}+\frac{7/2}{\sqrt{9+16}}=\frac{3}{2}$

Hence radius is $\frac{3}{4}$