Which of the following equations has two distinct real roots?

Same as the previous one. Let’s check the discriminant value for distinct real roots.

A. Given,


D = b2 - 4ac = 0



= 18 - 18 = 0


Hence, the roots are real and equal.


B. Given, x2 + x – 5 = 0


D = b2 - 4ac = 0


= (1)2 - 4(1) (-5)


= 1 + 20 = 21 > 0


Hence, the roots are real and distinct.


C. Given,


D = b2 - 4ac = 0


= 32 - 4(1) (2√2)



Hence, the roots are imaginary.


D. Given, 5x2 - 3x + 1 = 0


D = b2 - 4ac = 0


= (-3)2 - 4(5)(1)


= 9 – 20 < 0


Hence, the roots are imaginary.

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