If 6 is the root of the equation with variable x, it means x can take the value 6.
That is,
2x^2+3x-k=0
Substituting 6 for x,
2*6^2+3*6-k=0
72 + 18 -k =0
k =90
ps - quadratic root q
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Anurag@Gurome
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Since one of the roots is 6, so it will satisfy the given quadratic equation, 2x² + 3x - k = 0ccassel wrote:How would you explain the answer to this question?
If one root of the equation 2x^2+3x-k=0 is 6, what is the value of k?
A. 90
B. 42
C. 18
D. 10
E. -10
Answer is A
So, 2(6)² + 3(6) - k = 0 implies 90 - k = 0 or k = 90
The correct answer is A.
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manpsingh87
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f(x)=2x^2+3x-k; now if 6 is a factor of f(x) than f(x)=0; at x=6..!!!ccassel wrote:How would you explain the answer to this question?
If one root of the equation 2x^2+3x-k=0 is 6, what is the value of k?
A. 90
B. 42
C. 18
D. 10
E. -10
Answer is A
therefore we have 2*36+28-k=0; k=90..!!
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