Learn math, science, English SAT & ACT from
highquaility study
videos by expert teachers
Thank you for watching the preview.
To unlock all 5,300 videos, start your free trial.
Solving Quadratic Equations by Factoring  Problem 1
Alissa Fong
Alissa Fong
MA, Stanford University
Teaching in the San Francisco Bay Area
Alissa is currently a teacher in the San Francisco Bay Area and Brightstorm users love her clear, concise explanations of tough concepts
Here's a problem that I want to solve by factoring. So even if I don't know what solve means I know I’m going to have to start this problem by factoring. Since both of these terms have an x I’m going to factor out the greatest common factor which is x, it’s going to start looking like this. Like undistributing. X times what gives me x squared? And then I need x times what gives me 4x here we go so that's my factored form of that binomial.
Next thing I’m going to do in order to solve, solve means find what x values make the statement true. So what I’m going to do in order to do that is use this 0 product property that tells me that if the product of two things is equal to 0 then either of that first guys is equal to 0 or the second guy is equal to 0.
That's already going to be one of my solutions if x is 0 that should be equal to 0.My other solution is going to be 4. Because if I plug in 4 here and I do out the math I should get 0. I'm going to check just a little really quickly just to make sure.
The way to check is by substituting the x value to this original problem. Is it true that 0 squared plus 4 times 0 is 0? Yeah 0 plus 0 equals 0. Is it true that 4times itself plus 4 times 4 is equal to 0? It’s kind of messy plus 4 times 4 is it true that 16 take away 16 equals 0? Yeah that's right.
That's how I know I have my two correct solutions. So when you’re asked to solve something by factoring factor out your binomial trinomial looking for greatest common factor or by using factoring techniques then set each one equal to 0. And lastly be sure to check your work because there's no reason why you want to get these problems wrong because they are not too difficult.
Please enter your name.
Are you sure you want to delete this comment?
Alissa Fong
M.A. in Secondary Mathematics, Stanford University
B.S., Stanford University
Alissa has a quirky sense of humor and a relatable personality that make it easy for students to pay attention and understand the material. She has all the math tips and tricks students are looking for.
Sample Problems (22)
Need help with a problem?
Watch expert teachers solve similar problems.

Solving Quadratic Equations by Factoring
Problem 1 15,326 viewsSolve by factoring:
x² + 4x = 0 
Solving Quadratic Equations by Factoring
Problem 2 12,425 viewsSolve by factoring:
x² + 2x = 15 
Solving Quadratic Equations by Factoring
Problem 3 11,187 viewsSolve by factoring:
x² + 6x + 9 = 0 
Solving Quadratic Equations by Factoring
Problem 4 11,347 viewsSolve by factoring:
3x² − 18x = 27 
Solving Quadratic Equations by Factoring
Problem 5 1,774 views 
Solving Quadratic Equations by Factoring
Problem 6 1,744 views 
Solving Quadratic Equations by Factoring
Problem 7 1,519 views 
Solving Quadratic Equations by Factoring
Problem 8 1,451 views 
Solving Quadratic Equations by Factoring
Problem 9 1,435 views 
Solving Quadratic Equations by Factoring
Problem 10 1,479 views 
Solving Quadratic Equations by Factoring
Problem 11 1,339 views 
Solving Quadratic Equations by Factoring
Problem 12 1,426 views 
Solving Quadratic Equations by Factoring
Problem 13 1,345 views 
Solving Quadratic Equations by Factoring
Problem 14 1,542 views 
Solving Quadratic Equations by Factoring
Problem 15 1,335 views 
Solving Quadratic Equations by Factoring
Problem 16 697 views 
Solving Quadratic Equations by Factoring
Problem 17 714 views 
Solving Quadratic Equations by Factoring
Problem 18 614 views 
Solving Quadratic Equations by Factoring
Problem 19 663 views 
Solving Quadratic Equations by Factoring
Problem 20 657 views 
Solving Quadratic Equations by Factoring
Problem 21 663 views 
Solving Quadratic Equations by Factoring
Problem 22 657 views
Comments (0)
Please Sign in or Sign up to add your comment.
·
Delete