1.

Find the centre and radius of the circle `3x^(2) 3y^(2) - 6x +9y - 8 =0`.

Answer» `3x^(2)+3y^(2)-69y-8=0`
`rArrx^(2)+y^(2)-2x+3y-(8)/(3)=0`
Comparing with the general equation of the circle `x^(2)+y^(2) +2gx +c =0`
`2g=-2,2f=3 and c=-(8)/(3)`
`rArrg=-1,f=(3)/(2)and c=-(8)/(3)`
`:.` Centre of circle `= (-g,-f)`
`= (1,-(3)/(2))`
And radius of circle
`=sqrt(g^(2)+f^(2)-c)=sqrt(1+(9)/(4)-(-(8)/(3)))`
`=sqrt(1+(9)/(4)+(8)/(3))=sqrt((12+27+32)/(12))`
`= sqrt((71)/(12))=(sqrt(71))/(2sqrt(3))` units.


Discussion

No Comment Found

Related InterviewSolutions