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How many real roots does the quadratic function h(x) = -7x^2 + 10x - 5 have?

a. 0

b. 1

c. 2

d. 3

User Lvthillo
by
7.1k points

2 Answers

2 votes

Final Answer:

The quadratic function
\(h(x) = -7x^2 + 10x - 5\) has 2 real roots.

The discriminant \(Δ = -40\), being negative, indicates two complex conjugate roots. Consequently, there are no real roots for this quadratic function.

thus the correct option( c)

Step-by-step explanation:

The given quadratic function is in the form
\(ax^2 + bx + c\), where
\(a = -7\), \(b = 10\), and \(c = -5\). To determine the number of real roots, we can use the discriminant formula, \(Δ =
b^2 - 4ac\).

For this quadratic function, the discriminant is calculated as follows:

\[Δ =
(10)^2 - 4(-7)(-5)\]

\[Δ = 100 - 140\]

\[Δ = -40\]

Since the discriminant is negative (\(Δ < 0\)), the quadratic equation has two complex conjugate roots. The complex roots imply that there are no real roots for this quadratic function. Therefore, the correct answer is 2 (c. 2).

In a quadratic equation
\(ax^2 + bx + c = 0\), the discriminant \(Δ\) determines the nature of the roots. If \(Δ > 0\), there are two distinct real roots. If \(Δ = 0\), there is one real root (a repeated root). If \(Δ < 0\), as in this case, there are two complex conjugate roots. The discriminant essentially provides insight into the positioning of the roots on the real number line.

therefore correct option is( c)

User Juharr
by
7.3k points
2 votes

Final answer:

The correct answer is a. 0. By calculating the discriminant of the quadratic equation h(x) = -7x^2 + 10x - 5, which is negative, we can determine that the function has no real roots.

Step-by-step explanation:

The number of real roots of the quadratic function h(x) = -7x^2 + 10x - 5 can be determined by calculating the discriminant (b^2 - 4ac) from the quadratic equation ax^2 + bx + c = 0.

In this case, we have a = -7, b = 10, and c = -5. By substituting these values into the discriminant formula, we get discriminant = b^2 - 4ac = (10)^2 - 4(-7)(-5) = 100 - 140 = -40.

Since the discriminant is less than zero, it indicates that there are no real roots; the function has two complex roots.

Thus, the correct answer is a. 0.

User Starscream
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6.8k points