Roots and Coefficient of Quadratic Equations

​Roots and Coefficients of Quadratic Equations

​Objectives:

​1. Characterizes the roots of a quadratic equation using the discriminant.

 

2. Describes the relationship between the coefficients and the roots of a quadratic equation.

 

3. Write a quadratic equation given a pair of solutions

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​Solve each equation by using the quadratic formula.

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​Complete the table below.

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​Complete the table below.

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We use the discriminant to determine the number of real solutions of a quadratic equation. It also tells whether those solutions are either rational or irrational numbers.

Discriminant or D = b² - 4ac

Multiple Choice

If D = 0, the equations has ____ real solutions.

• 0

• 1

• 2

Multiple Choice

If D > 0 but not a perfect square, the quadratic equation is said to have 2 real solutions which are ______

• rational

• irrational

• imaginary

Multiple Choice

What is the discriminant of the quadratic equation 4x² - 5x - 9 = 0?

• 119

• 144

• 163

• 169

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​Complete the table below.

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​Complete the table below.

Multiple Choice

True or False.

The sum of the two roots can be computed by using $$\frac{c}{a}$$  .

• True

• False

Multiple Choice

What is the product of the roots of x² + 2x + 3 = 0?

• 3

• -3

• 2

• -2

Multiple Choice

What is the sum of the roots of 2x² - 3x = 4?

• 2

• -2

• 3/2

• -3/2

​Worktext Reference:

​Oronce O.A., Mendoza M.O. (2019). E-Math Worktext in Mathematics 9, Manila, Philippines: REX Bookstore Inc.