Find the radius of the circle x²+y²-4x-8y-45=0

Challenger App

★

1M+ Downloads

A√65

B√56

C√34

D√43

Answer:

x²+y²-2gx-2fy+c=0 2g = -4 ; g=-2 2f= -8 f= -4 c= -45 (h,k)= (-g,-f)=(2,4) radius= √(g²+f²-c)= √(-2)²+(-4)²-(-45))= √4+16+45=√65

Related Questions:

If x : y = 2 : 3 then the value of $\frac{3x+2y}{9x+5y}$ will be

If a + b + c = 6, a³ + b³ + c³ - 3 abc = 342, and a² + b² + c² = 50, then what is the value of ab + bc + ca?

$a^2+b^2=65$ , and $ab=8$ then find the value of $a^2-b^2$

If a + b + c = 7 and $a^3 + b^3 + c^3-3abc = 175$ , then what is the value of (ab + bc + ca)?