Q101 of 134 Page 4


Given that -3 and m are the roots of the quadratic equation kx 2+5x – 3 = 0. Find the value of m and of k.


Let us consider the given equation kx 2 + 5x – 3 = 0 in the form ax 2 + bx + c = 0.
Here a = k, b = 5, c = -3
The two roots are -3 and m. Thus sum of the roots are
and the product of the roots are -
-3k + km = -5 -------(1)
-
=> -3km = -3
=> km = 1
Substitute km = 1 in (1)
-3k + 1 = -5
-3k = -5 – 1 = -6 ∴ k = 2.
Thus by substituting k = 2 in km = 1 we get

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