Math, asked by ravneet5726, 1 year ago

If -5 is a root of the quadratic equation 2x^2 + px -15 = 0 and the quadratic equation p(x2 + x)+k =0 has equal roots,then find the value of k.

Answers

Answered by BEJOICE
4

given \:  \:  - 5 \:  \: is \:  \: a \:  \: root \\ so \:  \: 2 \times  {( - 5)}^{2}  + p \times  - 5 - 15 = 0 \\  - 5p =  - 35 \\ p = 7 \\  \\ p( {x}^{2}  + x) + k = 0 \\ 7 {x}^{2}  + 7x + k = 0 \:  \: has \:  \: equal \:  \: roots \\ so \:  \: discriminant = 0 \\  {7}^{2}  - 4 \times 7 \times k = 0 \\ k =  \frac{7}{4}
Answered by DeeptiMohanty
1
Hope this helps you......
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