## Algebra 2 Help: solving by completing square, graphing, etc

Quadratic equations and inequalities, variation equations, function notation, systems of equations, etc.

### Algebra 2 Help: solving by completing square, graphing, etc

I have some problems with my homework I cant figure out, can someone help me by giving me the answers.

1. What are the answers to the following equation when trying to complete the square:
3x^2+7x=-9

2. Determine the number of solutions in this equation: -4x^2-3x+7=0

3. Graph: y=x^2-4x+13
a. What is the Discrinate?
b. How many solutions?
c. What type of solutions does this equation have?

THANKS A TON!!!
michaelearth

Posts: 1
Joined: Fri Apr 17, 2009 2:02 am

michaelearth wrote:1. What are the answers to the following equation when trying to complete the square:
3x^2+7x=-9

To learn how to solve quadratics by completing the square, try here. Note that you can check your answers by using the more-reliable Quadratic Formula.

michaelearth wrote:2. Determine the number of solutions in this equation: -4x^2-3x+7=0

Since this asks you only for the number of solutions, not for the actual values of the solutions, you need to use the discriminant (the stuff inside the square root in the Quadratic Formula) to determine this. I don't know if you've studied complex numbers yet. If not, you'll only need to use what you've learned about positive and zero values. In either case, the three possible outcomes are listed and explained here.

michaelearth wrote:3. Graph: y=x^2-4x+13

To learn how to graph quadratics, try here.

michaelearth wrote:a. What is the Discrinate?
b. How many solutions?
c. What type of solutions does this equation have?

When the assignment misspells the word, it's no surprise when the students get stuck!

As displayed above, the intended term is of course "discriminant". So do the same for these parts as you did for part (2) above.

stapel_eliz

Posts: 1782
Joined: Mon Dec 08, 2008 4:22 pm