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What kind of roots does the quadratic equation 5x2+7x+4=05x^2 + 7x + 4 = 05x2+7x+4=0​ have?
Question

What kind of roots does the quadratic equation 5x2+7x+4=05x^2 + 7x + 4 = 0​ have?

A.

No real roots

B.

Only one real root

C.

Real and equal roots

D.

Real and unequal roots

Correct option is A

Given:

Given quadratic equation = 5x2+7x+4=05x^2 + 7x + 4 = 0​​

Formula Used:

For finding the nature of roots we use determinant D = b24ac b^2 - 4ac​ for any equation in form of ax2+bx+c=0ax^2 +bx +c = 0​​

If D =0 then real and equal roots

If D<0 then roots are imaginary or no real roots

If d>0 then roots are real and distinct

Solution:

Here in the equation 5x2+7x+4=05x^2 + 7x + 4 = 0​​

Here a =5 , b=7 and c = 4

So D =(7)24(5)(4)=4980=31 (7)^2 - 4(5)(4) = 49 - 80 = -31​​

Hence D = -31 < 0

So the roots are imaginary or no real roots

Hence option (a) is correct

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