Answer: (x - 4)² + (y - 7)² = 9
Explanation:
The equation of a circle is: (x - h)² + (y - k)² = r² where
- (h, k) is the center
- r is the radius
Given: (h, k) = (4, 7)
Find the intersection of the given equation and the perpendicular passing through (4, 7).
3x - 4y = -1
-4y = -3x - 1
[tex]y=\dfrac{3}{4}x-1[/tex]
[tex]m=\dfrac{3}{4}[/tex] --> [tex]m_{\perp}=-\dfrac{4}{3}[/tex]
[tex]y-y_1=m_{\perp}(x-x_1)\\\\y-7=-\dfrac{4}{3}(x-4)\\\\\\y=-\dfrac{4}{3}x+\dfrac{16}{3}+7\\\\\\y=-\dfrac{4}{3}x+\dfrac{37}{3}[/tex]
Use substitution to find the point of intersection:
[tex]x=\dfrac{29}{5}=5.8,\qquad y=\dfrac{23}{5}=4.6[/tex]
Use the distance formula to find the distance from (4, 7) to (5.8, 4.6) = radius
[tex]r=\sqrt{(5.8-4)^2+(4.6-7)^2}\\\\r=\sqrt{3.24+5.76}\\\\r=\sqrt9\\\\r=3[/tex]
Input h = 4, k = 7, and r = 3 into the circle equation:
(x - 4)² + (y - 7)² = 3²
(x - 4)² + (y - 7)² = 9
