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If the Roots of the Quadratic Equation `2x^2+8x+K=0` Are Equal Then Find the Value of K. - Mathematics

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Question

If the roots of the quadratic equation `2x^2+8x+k=0` are equal then find the value of k.  

Solution

It is given that the roots of the quadratic equation `2x^2+8x+k=0` 

are equal. 

∴`D=0` 

⇒`8^2-4xx2xxk=0` 

⇒`64-8k=0` 

⇒`k=8` 

Hence, the value of k is `8`.

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Chapter 10: Quadratic Equations - Exercises 6

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RS Aggarwal Mathematics [English] Class 10
Chapter 10 Quadratic Equations
Exercises 6 | Q 38

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