Leslie said that a circle with equation (x - 2)2 + (y - 7)2 = 13 has a tangent line represented by "y - 5 = -3/2(x + 1)". Right or wrong?

ava27 May 5, 2020

#1**+1 **

(x -2)^2 + (y - 7)^2 = 13

The center = ( 2, 7)

y = (-3/2)(x + 1) + 5

This would mean the the point ( -1, 5) is on the circle (which is true) because (-1-2)^2 + (5-7)^2 =

3^2 + 2^2 = 13

It also means that the slope of the line containing the center and this point is

[ 7-5] / [ 2 - -1] = 2/3

The tangent line line at (-1.5) would have a slope of -3/2

Looks like Leslie is correct !!!

CPhill May 5, 2020