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What is the value of the discriminant for the quadratic equation 0 equals X squared minus 4X +5 and how many number of real solutions does the equation have

2 Answers

4 votes

Answer:-5

Explanation:

User Alireza Amini
by
2.6k points
6 votes

Answer:

Discriminant: -4

No real solutions

Explanation:

You might remember this long, seemingly very hairy thing called the quadratic formula from earlier in algebra:


x=(-b\pm√(b^2-4ac))/(2a)

The discriminant of a quadratic equation of the form
ax^2+bx+c=0 is that bit under the square root:
b^2-4ac. What does the discriminant tell us? Since we're taking its square root, we know that
√(b^2-4ac) is only real for non-negative values of
b^2-4ac. If
b^2-4ac > 0, we have two real roots, one for
√(b^2-4ac) and one for
-√(b^2-4ac). If
b^2-4ac = 0, the function has a rational root, since the formula becomes


x=(-b)/(2a)

In your case, we have the equation
x^2-4x+5; here,
a=1,
b=-4, and
c=5, so our discriminant is
(-4)^2-4(1)(5)=16-20=-4. Since we'd have a negative under our square root in the quadratic formula, we have no real solutions.

User LeoE
by
3.3k points