Grade 12Analytical GeometryX²+Y²+Z²-2X+4Y-4Z+k=0 is an equation of sphere, then k could be ........ Nermin Salah 9 Years agoGrade 12
Vikas TU9 Years agoBy rearranging the equation of sphere(X-1)2 -1 + (Y+2)2 -4 +(Z-2)2 -4 +k=0(X-1)2 + (Y+2)2 +(Z-2)2 -9 +k=0Hence -9 + k = r2 Where r is the radius of the sphere.Hence r =(k-9)^1/2Hence k-9 should be positive.k is greater than 9