Question

What is the length of a radius of a circle whose center is at (1, -2) and whose one point lies on a circle at (-5, 6)?

Answer 1

radius = 10

Explanation:

The distance from the centre to the point on the circle is the radius r

Calculate r using the distance formula

r =
`\sqrt{(x_(2)-x_(1))^2+(y_(2)-y_(1))^2 }`

with (x₁, y₁ ) = (1, - 2) and (x₂, y₂ ) = (- 5, 6)

r =
`√((-5-1)^2+(6-(-2))^2)`

=
`√((-6)^2+(6+2)^2)`

=
`√(36+8^2)`

=
`√(36+64)`

=
`√(100)`

= 10