Algebra II : Quadratic Equations and Inequalities

Study concepts, example questions & explanations for Algebra II

varsity tutors app store varsity tutors android store

Example Questions

Example Question #141 : Understanding Quadratic Equations

Given , what is the value of the discriminant?

Possible Answers:

Correct answer:

Explanation:

The correct answer is . The discriminant is equal to  portion of the quadratic formula. In this case, "" corresponds to the coefficient of , "" corresponds to the coefficient of , and "" corresponds to . So, the answer is , which is equal to

Example Question #301 : Intermediate Single Variable Algebra

Find the value of the discriminant and state the number of real and imaginary solutions.

Possible Answers:

57, 2 real solutions

57, 2 imaginary solutions

-7, 2 real solutions

-7, 2 imaginary solutions

57, 1 real solution

Correct answer:

57, 2 real solutions

Explanation:

Given the quadratic equation of 

The formula for the discriminant is  (remember this as a part of the quadratic formula?)

Plugging in values to the discriminant equation:

So the discriminant is 57. What does that mean for our solutions? Since it is a positive number, we know that we will have 2 real solutions. So the answer is:

57, 2 real solutions

Example Question #1 : Quadratic Roots

Give the solution set of the equation .

Possible Answers:

Correct answer:

Explanation:

Using the quadratic formula, with :

Example Question #1 : Quadratic Roots

Give the solution set of the equation  .

Possible Answers:

Correct answer:

Explanation:

Using the quadratic formula, with :

Example Question #142 : Understanding Quadratic Equations

Write a quadratic equation in the form  with 2 and -10 as its roots.

Possible Answers:

Correct answer:

Explanation:

Write in the form  where p and q are the roots.

Substitute in the roots:

Simplify:

Use FOIL and simplify to get

.

Example Question #4 : Quadratic Roots

Find the roots of the following quadratic polynomial:

Possible Answers:

This quadratic has no real roots.

Correct answer:

Explanation:

To find the roots of this equation, we need to find which values of  make the polynomial equal zero; we do this by factoring. Factoring is a lot of "guess and check" work, but we can figure some things out. If our binomials are in the form , we know  times  will be  and  times  will be . With that in mind, we can factor our polynomial to 

To find the roots, we need to find the -values that make each of our binomials equal zero. For the first one it is , and for the second it is , so our roots are .

Example Question #143 : Understanding Quadratic Equations

Write a quadratic equation in the form  that has  and  as its roots.

Possible Answers:

Correct answer:

Explanation:

1. Write the equation in the form  where  and  are the given roots.

 

2. Simplify using FOIL method.

Example Question #2 : Quadratic Roots

Give the solution set of the following equation:

Possible Answers:

Correct answer:

Explanation:

Use the quadratic formula with  and :

 

 

Example Question #1 : Quadratic Roots

Give the solution set of the following equation:

Possible Answers:

Correct answer:

Explanation:

Use the quadratic formula with , and :

Example Question #144 : Understanding Quadratic Equations

Let

Determine the value of x.

Possible Answers:

Correct answer:

Explanation:

To solve for x we need to isolate x. We can do this by taking the square root of each side and then doing algebraic operations.

Now we need to separate our equation in two and solve for each x.

     or     

                     

Learning Tools by Varsity Tutors