Find the value of k for which the lines 5x + 4y - 6 = 0 and 2x + ky + 9 = 0 are (ii) perpendicular.

Find the value of k for which the lines 5x + 4y - 6 = 0 and 2x + ky + 9 = 0 are (i) parailel,

Answer the question Find the value of lamda for which the planes 2x - 4y + 3z = 7 and x + 2y + lamda z = 18 are perpendicular to each other.

Find the value of m for which the lines 4x -3y - 1 = 0, 3x - 4y + 1 = 0 and mx - 7y + 3 = 0 are concurrent.

Find the value of k for which the line x + 2y + k = 0 touches the circle x ^2 + y ^2 = 5.

Find the equation of straight line passing through the point of intersection of the straight lines 2x - 3y + 4 = 0 and x + 2y - 5 = 0 and perpendicular to the line 3x - 4y + 5 = 0.

Find the value of x for which x^2-7x , x^2+9 and 6 are in A.P.

Find the equation of the tangents to the circle x ^2 + y ^2 - 2x - 4y - 4 = 0 which are perpendicular to the line 3x - 4y - 1 = 0

Find the value of k for which the pair of linear equation kx+3y=k-2 and 12x+ky=k has no solution.

A straight line passes through the point of intersection of the straight lines 3x - 2y + 4 = 0 and 2x + 3y +5 = 0 and is parallel to the straight line x -y + 5 = 0. Find its equation.

Find the equation of the tangents to the ellipse 3x ^2 + 4y ^2 = 12 which are perpendicular to the line 2x +y - 4 = 0.