If P(-9,-1) is a point on the circle x^2+y^2+ | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The given circle is $x^2+y^2+4x+8y-38=0$. Completing the square,we get $(x+2)^2+(y+4)^2=58$. The center of the circle is $C(-2,-4)$. Let $Q(x_1, y

Vedclass · Accepted Answer

$7x-3y=56$

Vedclass · Answer

(B) The given circle is $x^2+y^2+4x+8y-38=0$. Completing the square,we get $(x+2)^2+(y+4)^2=58$. The center of the circle is $C(-2,-4)$. Let $Q(x_1, y_1)$ be the other end of the diameter passing through $P(-9,-1)$. Since $C$ is the midpoint of $PQ$,we have $\frac{x_1-9}{2}=-2 \Rightarrow x_1=5$ and $\frac{y_1-1}{2}=-4 \Rightarrow y_1=-7$. Thus,$Q$ is $(5,-7)$. The tangent at $Q$ is parallel to the tangent at $P$. The slope of the radius $CP$ is $m_{CP} = \frac{-1-(-4)}{-9-(-2)} = \frac{3}{-7} = -\frac{3}{7}$. The slope of the tangent at $P$ (and $Q$) is the negative reciprocal of the slope of the radius,which is $m = -\frac{1}{-3/7} = \frac{7}{3}$. The equation of the tangent at $Q(5,-7)$ is $y - (-7) = \frac{7}{3}(x - 5)$. $3(y+7) = 7(x-5)$ $\Rightarrow 3y+21 = 7x-35$ $\Rightarrow 7x-3y=56$.

If $P(-9,-1)$ is a point on the circle $x^2+y^2+4x+8y-38=0$,then find the equation of the tangent drawn at the other end of the diameter drawn through $P$.

Similar Questions

The area of the triangle formed by the tangent at $(3, 4)$ to the circle ${x^2} + {y^2} = 25$ and the coordinate axes is

The equation of a line parallel to the line $3x + 4y = 0$ and touching the circle $x^{2} + y^{2} = 9$ in the first quadrant is:

The angle between the two tangents from the origin to the circle $(x - 7)^2 + (y + 1)^2 = 25$ is

The equation of the tangent to the circle $x^2 + y^2 - 22x - 4y + 25 = 0$ which is perpendicular to the line $5x + 12y + 8 = 0$ is:

If $y=3x$ is a tangent to a circle with centre $(1,1)$,then the other tangent drawn through $(0,0)$ to the circle is

Vedclass Test Series

Exam Paper Generator

Online Exam Module