pair-st-lines

Related Questions

• If the equation $2{{x}^{2}}+7xy+3{{y}^{2}}-9x-7y+k=0$ represents a pair of lines, then k is equal to

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• The gradient of one of the lines of $a{{x}^{2}}+2hxy+b{{y}^{2}}=0$ is twice that of the other, then

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• The equation $12{{x}^{2}}+7xy+a{{y}^{2}}+13x-y+3=0$ represents a pair of perpendicular lines. Then the value of ‘a’ is

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• The straight lines represented by the equation $9{{x}^{2}}-12xy+4{{y}^{2}}=0$ are

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• If the angle $2\theta $is acute, then the acute angle between ${{x}^{2}}(\cos \theta -\sin \theta )+2xy\cos \theta +{{y}^{2}}(\cos \theta +\sin \theta )=0$ is

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