Question

prove that the point (-1'2)is a centre of a circle passing through the point (-3,11) (5'9) (8,0) and (6,8) find the radius of this circle <br />​

Answer 1

Answer:

Step-by-step explanation:

1). A circle is the set of all points on a plane that are a fixed distance from a center.

2). d = √[($x_{1}$ - $x_{2}$)² + ($y_{1}$ - $y_{2}$)²]

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$d_{1}$ = $\sqrt{(-1+3)^2+(2-11)^2}$ = √85

$d_{2}$ = $\sqrt{(-1-5)^2+(2-9)^2}$ = √85

$d_{3}$ = $\sqrt{(-1-8)^2+(2-0)^2}$ = √85

$d_{4}$ = $\sqrt{(-1-6)^2+(2-8)^2}$ = √85

$d_{1}$ = $d_{2}$ = $d_{3}$ = $d_{4}$ = r ⇒ (- 1, 2) is a center of a circle

r = √85