Aman saves money so that the equation x^2 + 2(k+3)x + (k+8) = 0 (modelling two equal yearly targets) has equal roots. Set up D = 0 to get a quadratic in k, then find the sum of the possible values of k.

Question

Accepted Answer

-5. D = 0: [2(k+3)]^2 - 4(k+8) = 0 => 4(k+3)^2 - 4(k+8) = 0 => (k+3)^2 - (k+8) = 0 => k^2 + 6k + 9 - k - 8 = 0 => k^2 + 5k + 1 = 0. Sum of the values of k = -b/a = -5/1 = -5.

Aman saves money so that the equation $x^{2} + 2 (k + 3) x + (k + 8) = 0$ (modelling two equal yearly targets) has equal roots.
Set up $D = 0$ to get a quadratic in $k$ , then find the sum of the possible values of $k$ .

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More Class 10 Nature of Roots (Discriminant) practice

Aman saves money so that the equation x2+2(k+3)x+(k+8)=0 (modelling two equal yearly targets) has equal roots.Set up D=0 to get a quadratic in k, then find the sum of the possible values of k.

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 10 Nature of Roots (Discriminant) practice

Aman saves money so that the equation $x^{2} + 2 (k + 3) x + (k + 8) = 0$ (modelling two equal yearly targets) has equal roots.
Set up $D = 0$ to get a quadratic in $k$ , then find the sum of the possible values of $k$ .