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The coefficient of x in the equation \( \Large x^{2}+px+q=0 \) was taken as 17 in place of 13 its roots Were found to be -2 and -15. The roots of the original equation are:

A) 3,10
B) -3 , -10
C) -5, -8
D) None of these

Correct Answer:


B) -3 , -10

Description for Correct answer:
Let the equation (incorrectly written form)

be \( \Large x^{2}+17x+q=0 \)

since, roots are -2, -15

Therefore, q = 30

so, correct equation is \( \Large x^{2}+13x+30=0 \)

=> \( \Large x^{2}+10x+3x+30=0 \)

=> \( \Large \left(x+3\right) \left(x+10\right)=0 \)

=> x = -3, -10

Part of solved Quadratic Equations questions and answers : >> Elementary Mathematics >> Quadratic Equations

Comments

Similar Questions

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