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if the line 4x +3y +1=0 meets the parabo...

if the line `4x +3y +1=0` meets the parabola `y^2=8x` then the mid point of the chord is

A

`(2,- 3)`

B

`(2,4)`

C

`(5//2, 14//3)`

D

`(5, 8)`

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To find the midpoint of the chord formed by the intersection of the line \(4x + 3y + 1 = 0\) and the parabola \(y^2 = 8x\), we can follow these steps: ### Step 1: Express \(y\) in terms of \(x\) from the line equation The line equation is given as: \[ 4x + 3y + 1 = 0 \] We can rearrange this to express \(y\): \[ 3y = -4x - 1 \implies y = -\frac{4}{3}x - \frac{1}{3} \] **Hint:** Rearranging the equation helps isolate one variable, making substitution easier. ### Step 2: Substitute \(y\) into the parabola equation Now, substitute \(y\) from the line equation into the parabola equation \(y^2 = 8x\): \[ \left(-\frac{4}{3}x - \frac{1}{3}\right)^2 = 8x \] Expanding the left side: \[ \left(\frac{16}{9}x^2 + \frac{8}{9}x + \frac{1}{9}\right) = 8x \] **Hint:** Squaring a binomial involves applying the formula \((a + b)^2 = a^2 + 2ab + b^2\). ### Step 3: Clear the fraction and rearrange the equation Multiply through by 9 to eliminate the denominator: \[ 16x^2 + 8x + 1 = 72x \] Rearranging gives: \[ 16x^2 - 64x + 1 = 0 \] **Hint:** Clearing fractions simplifies the equation and makes it easier to work with. ### Step 4: Use the quadratic formula to find \(x\) We can find the roots \(x_1\) and \(x_2\) using the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] Here, \(a = 16\), \(b = -64\), and \(c = 1\): \[ x = \frac{64 \pm \sqrt{(-64)^2 - 4 \cdot 16 \cdot 1}}{2 \cdot 16} \] Calculating the discriminant: \[ x = \frac{64 \pm \sqrt{4096 - 64}}{32} = \frac{64 \pm \sqrt{4032}}{32} \] **Hint:** The quadratic formula is a powerful tool for finding roots of any quadratic equation. ### Step 5: Find the sum of the roots From Vieta's formulas, the sum of the roots \(x_1 + x_2\) is given by: \[ x_1 + x_2 = -\frac{b}{a} = \frac{64}{16} = 4 \] **Hint:** Vieta's formulas relate the coefficients of the polynomial to sums and products of its roots. ### Step 6: Find the midpoint of the chord The x-coordinate of the midpoint \(M\) is: \[ M_x = \frac{x_1 + x_2}{2} = \frac{4}{2} = 2 \] **Hint:** The midpoint formula for coordinates is simply the average of the x-coordinates and y-coordinates of the endpoints. ### Step 7: Find the y-coordinate of the midpoint To find the y-coordinate of the midpoint, we can use the line equation to find \(y\) when \(x = 2\): \[ y = -\frac{4}{3}(2) - \frac{1}{3} = -\frac{8}{3} - \frac{1}{3} = -\frac{9}{3} = -3 \] **Hint:** Substituting the x-coordinate back into the line equation gives the corresponding y-coordinate. ### Final Answer Thus, the midpoint of the chord is: \[ \boxed{(2, -3)} \]

To find the midpoint of the chord formed by the intersection of the line \(4x + 3y + 1 = 0\) and the parabola \(y^2 = 8x\), we can follow these steps: ### Step 1: Express \(y\) in terms of \(x\) from the line equation The line equation is given as: \[ 4x + 3y + 1 = 0 \] We can rearrange this to express \(y\): ...
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OBJECTIVE RD SHARMA ENGLISH-PARABOLA-Chapter Test
  1. if the line 4x +3y +1=0 meets the parabola y^2=8x then the mid point o...

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  2. If y=2x+k is a tangent to the curve x^(2)=4y, then k is equal to

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  3. The normal drawn at a point (a t1 2,-2a t1) of the parabola y^2=4a x m...

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  4. The mid-point of the chord 2x+y-4=0 of the parabola y^(2)=4x is

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  5. The two ends of latusrectum of a parabola are the points (3, 6) and (-...

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  6. Prove that the locus of the middle points of all chords of the parabol...

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  7. The focus of the parabola x^2-8x+2y+7=0 is

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  8. The point of contact of the line x-2y-1=0 with the parabola y^(2)=2(x-...

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  9. Find the number of distinct normals that can be drawn from (-2,1) to t...

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  10. At what point on the parabola y^2=4x the normal makes equal angle with...

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  11. Three normals to the parabola y^2= x are drawn through a point (C, O) ...

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  12. The normal chord of a parabola y^2= 4ax at the point P(x1, x1) subten...

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  13. AB, AC are tangents to a parabola y^2=4ax; p1, p2, p3 are the lengths...

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  14. The circles on the focal radii of a parabola as diameter touch: A) th...

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  15. If the normals from any point to the parabola y^2=4x cut the line x=2 ...

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  16. about to only mathematics

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  17. The equation of the tangent to the parabola y^(2)=8x which is perpendi...

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  18. the tangent drawn at any point P to the parabola y^2= 4ax meets the di...

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  19. about to only mathematics

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  20. The parabola y^(2)=4ax passes through the point (2,-6). Find the lengt...

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  21. A variable circle passes through the fixed point (2, 0) and touches y-...

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