Question 1070237
The line with equation 4x+5y=7 is a tangent to a circle of radius r. Find the radius r if the equation of the circle is given by x^2+y^2=r^2
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The center is the Origin.
The distance from (0,0) to 4x+5y-7 = 0 is
|Ax + By + C|/(A^2 + B^2)
= 7/sqrt(41)
r = {{{7sqrt(41)/41}}}