Question

Which of the following pair of planes are parallel?
(a) 7x + 5y + 6z + 30 = 0 & 3x - y -10z + 4 = 0
(b) 2x + y +3z - 2 = 0 & x - 2y + 5 = 0
(c) 2x - 2y + 4z + 5 = 0 & 4x - 4y + 8z -1 = 0
(d) none of these

Answer 1

The following condition should be satisficed by them to be parallel-

$\frac{a_{1} }{a_{2} } =\frac{b_{1} }{b_{2} }\neq \frac{c_{1} }{c_{2} }$

ANSWER - (D) NONE OF THESE

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