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Question
Find the values of x if p + 1 =0 and x2 + px – 6 = 0
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Solution
p + 1 = 0, then p = – 1
Substituting the value of p in the given quadratic equation
x2 + ( – 1)x – 6 = 0
⇒ x2 – x – 6 = 0
⇒ x2 – 3x + 2x – 6 = 0
⇒ x(x – 3) + 2(x – 3) = 0
⇒ (x – 3) (x + 2) = 0
Either x – 3 = 0,
then x = 3
or
x + 2 = 0,
then x = – 2
Hence x = 3, -2.
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