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If a chord, which is not a tangent, of t...

If a chord, which is not a tangent, of the parabola `y^(2)=16x` has the equation 2x+y=p, and midpoint (h,k), then which of the following is (are) possible value(s) of p,h and k ?

A

p=5, h=4, k=-3

B

p=-1, h=1, k=-3

C

p=-2, h=2, k=-4

D

p=2, h=3, k=-4

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To solve the problem, we need to find the possible values of \( p \), \( h \), and \( k \) given the conditions of the chord of the parabola \( y^2 = 16x \) and the equation of the chord \( 2x + y = p \). ### Step-by-step Solution: 1. **Identify the Parabola and Chord Equation**: The equation of the parabola is given as: \[ y^2 = 16x \] The equation of the chord is given as: \[ 2x + y = p \] 2. **Assume the Midpoint**: Let the midpoint of the chord be \( (h, k) \). 3. **Equation of the Chord in Terms of Midpoint**: The equation of the chord passing through the midpoint can be expressed using the parametric form of the parabola. The equation can be derived as: \[ y(k - 8) = 16(h - x) \] Rearranging gives: \[ ky - 8x = k^2 - 16h \] 4. **Comparing the Two Chord Equations**: We have two equations: - From the chord equation: \( 2x + y = p \) - From the midpoint equation: \( ky - 8x = k^2 - 16h \) We can rewrite the chord equation as: \[ y = p - 2x \] Substituting this into the midpoint equation: \[ k(p - 2x) - 8x = k^2 - 16h \] Simplifying gives: \[ kp - 2kx - 8x = k^2 - 16h \] Rearranging terms results in: \[ (8 + 2k)x = kp - k^2 + 16h \] 5. **Setting Conditions for a Chord**: For the line to be a chord and not a tangent, the discriminant of the resulting quadratic equation must be positive. This leads to the conditions: \[ \frac{k}{1} = \frac{-8}{2} = \frac{k^2 - 8h}{p} \] 6. **Finding Relations**: From the above equations, we can derive: \[ k = -4 \quad \text{(since } k = -8/2 \text{)} \] Substituting \( k = -4 \) into the equation: \[ -4^2 - 8h = -4p \] This simplifies to: \[ 16 - 8h = -4p \] Rearranging gives: \[ 4p = 8h - 16 \quad \Rightarrow \quad p = 2h - 4 \] 7. **Finding Possible Values**: Now we can test possible integer values for \( h \): - If \( h = 2 \): \[ p = 2(2) - 4 = 0 \] - If \( h = 3 \): \[ p = 2(3) - 4 = 2 \] Thus, we have two sets of values: - For \( h = 2 \), \( p = 0 \), \( k = -4 \) - For \( h = 3 \), \( p = 2 \), \( k = -4 \) ### Conclusion: The possible values of \( (p, h, k) \) are: 1. \( (0, 2, -4) \) 2. \( (2, 3, -4) \)

To solve the problem, we need to find the possible values of \( p \), \( h \), and \( k \) given the conditions of the chord of the parabola \( y^2 = 16x \) and the equation of the chord \( 2x + y = p \). ### Step-by-step Solution: 1. **Identify the Parabola and Chord Equation**: The equation of the parabola is given as: \[ y^2 = 16x ...
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