Question

Znajdź środek i promień okręgu o równaniu.

Answer 1

x²+y²-2ax-2by+c=0

-2a=-4

a=-4;-2

a=2

.........

-2b=6

b=6;(-2)

b=-3

............

c=-12

 

S=(a,b)

S=(2;-3)

 

r²=2²+(-3)²+12

r=√25

r=5=promień

 

Answer 2

x^2 + y^2 - 2ax - 2by + a^2 + b^2 - r^2 = 0 ----- wzór

c = a^2 + b^2 - r^2

 

-2a = -4

a = 2

 

-2b = 6

b = -3

 

S = (a,b ) = (2,-3) --- środek

 

a^2 + b^2 - r^2 = c

2^2 + (-3)^2 - r ^2= -12

4 + 9 - r^2 = -12

13 + 12 = r^2

25 = r^2

r = 5 --- promień