Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
MHT CET202527 Apr 2025Evening ShiftMathematicsCircleActual

The equation of the common tangent touching the circle (x-3)^2+ y ^2=9 and the parabola y ^2=4 x above the X -axis is

Options

  1. A(4,2,1)
  2. B(4,-2,-1)
  3. C(-4,-2,-1)
  4. D(-4,-2,1)

Correct answer

A. (4,2,1)

Step-by-step solution

Equation of tangent to parabola. Given y^2 = 4x with a=1 , the general tangent above the X-axis is y = mx + 1 m , with m>0 . Condition for circle tangency. Circle (x-3)^2 + y^2 = 9 has center (3,0) and radius 3 . A line is tangent if the perpendicular distance from center to line equals 3 . For the line in form mx - y + 1 m = 0 , this distance is |3m + 1 m | m^2 + 1 = 3 . Since m>0 and 3m^2+1>0 , the equation simplifies to 3m^2 + 1 m m^2 + 1 = 3 . Squaring both sides and simplifying yields 3m^2 = 1 , so m = 1 3 (ta

Practice Circle on Quantrex Academy →

More from Circle

A circle touches both the coordinate axes and the straight line L 4 x +3 y -6=0 in the first quadrant. If this circle lies below the line L =0 , then the equation of that circle is 2025If the smallest circle through the points of intersection of x^2+y^2=a^2 and x +y =p, 0 < p < a is x^2+y^2-a^2+ (x +y -p)=0 then = 2025If the lines 3 x-4 y+4=0 and 6 x-8 y-7=0 are the tangents to the same circle, then the area of that circle (in sq.units) is 2025Circles are drawn through the point (2,0) to cut intercepts of length 5 units on the X -axis. If their centre lie in the first quadrant, then their equation is 2025The circles x^2+y^2-2 x-4 y-4=0 and x^2+y^2+2 x+4 y-11=0 2025If the line 4 x-3 y+7=0 touches the circle x^2+y^2-6 x+4 y-12=0 at ( , ) , then +2 = 2025The slope of the common tangent drawn to the circles x^2+y^2-4 x+12 y-216=0 and x^2+y^2+6 x-12 y+36=0 is 2025If r₁ and r₂ are radii of two circles touching all the four circles (x r)^2+(y r)^2=r^2 , then r₁+r₂ r = 2025 Full Circle list All MHT CET PYQs