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x2 + 2x + 5 = 0 is already in the form ax2 + bx + c = 0 so to find the discriminant, D, you use

D = b2 - 4ac

Then if D is greater than 0 the equation has 2 real roots; if D = 0 the equation has one real root and if D is less than 0 the equation has no real roots. So to check this we work out D but we need to know what a, b and c are. From the equation we can see that

a = 1

b = 2

c = 5

so putting these values in to find D:

D = (2)2 - 4(1)(5) = 4 - 20 = -16

so the equation x2 + 2x + 5 = 0 has no real roots.

Q: Use the discriminant to determine the real roots How many roots are in this problemx2 plus 2x plus 5 equals 0?

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The discriminant is -27 and so there are no real roots.

Child stop trying to cheat on your homework!

It has no real roots.

If the discriminant is negative, the roots will be two unreal complex conjugates. If the discriminate is positive the roots will be real.

If the discriminant of the quadratic equation is zero then it will have 2 equal roots. If the discriminant of the quadratic equation is greater than zero then it will have 2 different roots. If the discriminant of the quadratic equation is less than zero then it will have no roots.

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No real roots

The discriminant is -27 and so there are no real roots.

General form of a quadratic equation is: ax2+b+c = 0 The discriminant is: b2-4ac If the discriminant equals zero then there are two equal roots If the discriminant is greater than zero then there are two different roots If the discriminant is less than zero then there are no real roots

Child stop trying to cheat on your homework!

It has no real roots.

If you mean b^2 -4ac then it is the discriminant of a quadratic equation. If the discriminant equals 0 then the equation has 2 equal roots. If the discriminant is greater than 0 then the equation has 2 different roots. If the discriminant is less than 0 then it has no real roots.

If the discriminant of a quadratic equation is zero then it has equal roots. If the discriminant is greater than zero then there are two different roots. If the discriminant is less than zero then there are no real roots.

The discriminant of a quadratic equation helps determine the nature of its roots - whether they are real and distinct, real and equal, or imaginary.

If the discriminant is negative, the roots will be two unreal complex conjugates. If the discriminate is positive the roots will be real.

If the discriminant b2-4ac of a quadratic equation is less than zero then it will have no roots

If the discriminant of the quadratic equation is zero then it will have 2 equal roots. If the discriminant of the quadratic equation is greater than zero then it will have 2 different roots. If the discriminant of the quadratic equation is less than zero then it will have no roots.

If the discriminant of a quadratic equation is 0 then it has two equal real roots.