Math, asked by krit02, 1 year ago

Plz answer this question really i will mark the answer as brainlist
In this question u have to find value of K for which given equation has real and equal roots

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Answered by BEJOICE
1
For a quadratic equation, roots are real and equal if it's discriminant is 0
 {(2(1 + 3k))}^{2}  - 4 \times 1 \times 7(3 + 2k) = 0 \\ 4(1 + 6k + 9 {k}^{2} ) - 28(3 + 2k) = 0 \\ 36 {k}^{2}  - 32k - 80 = 0 \\ 9 {k}^{2}  - 8k - 20 = 0 \\ k =  \frac{8 + \: or \:  -   \sqrt{ { - 8}^{2}  - 4 \times 9 \times  - 20} }{2 \times 9}  \\ k =  \frac{8 +  \: or \:  - 28}{18}  \\ k =  \frac{36}{18}  \:  \: or \:  \:  \frac{ - 20}{18}  \\ k = 2 \:  \: or \:  \:  \frac{ - 10}{9}
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