• 100% Satisfaction Guarantee

SteveS, MBA
Category: Homework
Satisfied Customers: 453
Experience:  MBA from Top 5 US Business School, Tutoring Experience for Over Two Years
18851589
SteveS is online now

# My daughter is being taught the X method of factoring. In

### Resolved Question:

My daughter is being taught the "X" method of factoring. In her homework is the problem(3x squared - 5x - 2 = 0) The constant is -2, the co-efficient is -5. Since 2 is a prime, the only factors possible are 1 x -2 or -1 x 2, neither of which can be added together to achieve -5. How do we solve this problem, or what are we missing?
Submitted: 5 years ago.
Category: Homework
Expert:  SteveS replied 5 years ago.

You need to look at the first coefficient and the last coefficient when factoring a trinomial. Please take a look at the attached Word document that illustrates the solution to this problem, thanks!

Customer: replied 5 years ago.
In the example, the first coefficient is 3, but the second is -5, the constant is -2. My daughter was taught to put the constant in the top of the X, and the second coefficient in the bottom of the X, then find the factors that would multiply to produce the number in the top of the X, and add to produce the number in the bottom. These two numbers are then entered on either side of the X. These then become the factors that solve the equation.
Expert:  SteveS replied 5 years ago.

You can think of it this way (and refer to the attachment):

-on the left side of the X, place the two factors that make up the 1st coefficient -3. It's either going to be 1 and 3 or 3 and 1.

-on the right side of the X, place the two factors that make up the 3rd coefficient -2. It's going to be 2 and -1 or -2 and 1.

-Now is the time to select the correct factors out of the options you have. You do this by cross-multiplying and adding to get the 2nd coefficient, -5. To cross-multiply, take the number on the top-left of the X and multiply by the number on the bottom-right of the X. Also take the number on the top-right number of the X and multiply by the bottom-left of the X. Then add these two numbers. If you use the highlighted factors, you get 1*1 + -2*3 = 1 - 6 = -5. This is how you choose the correct factors.

-For the final step, all you need to do is fill in the factors into the equation (1x-2)*(3x+1). The top left factor and top right factor go into the first set (1x-2) and the bottom left factor and bottom right factor go into the 2nd set (3x+1).

Customer: replied 5 years ago.
Dear XXXXX: Apparently we are using two different versions of the technique. You refer to "top left" and "bottom right". Her teacher insists on her using the described technique of using the constant in the center top of the x, the second coefficient in the center bottom, cross-multiplying whatever factors produce the top number as well as add together to produce the bottom number. I can see that with the method you are using the factoring works and the problem is solved. But how can she achieve the same answer using the teacher's described technique? She has several problems that don't work this way, and several that do. So is this technique only applicable where the constant can be factored into numbers that add together to produce the 2nd coefficient? Other techniques must be used if this isn't possible?
Expert:  SteveS replied 5 years ago.

You need to spend \$3 to view this post. Add Funds to your account and buy credits.
SteveS, MBA
Category: Homework
Satisfied Customers: 453
Experience: MBA from Top 5 US Business School, Tutoring Experience for Over Two Years

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

### What Customers are Saying:

• Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C. Freshfield, Liverpool, UK
< Previous | Next >
• Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C. Freshfield, Liverpool, UK
• This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!! Alex Los Angeles, CA
• Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult. GP Hesperia, CA
• I couldn't be more satisfied! This is the site I will always come to when I need a second opinion. Justin Kernersville, NC
• Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around. Esther Woodstock, NY
• Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know. Robin Elkton, Maryland
• He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here. Diane Dallas, TX

• ### LogicPro

#### Satisfied Customers:

4925
Expert in Java C++ C C# VB Javascript Design SQL HTML
< Last | Next >

### LogicPro

#### Satisfied Customers:

4925
Expert in Java C++ C C# VB Javascript Design SQL HTML

### Manal Elkhoshkhany

#### Satisfied Customers:

4538
More than 5000 online tutoring sessions.

### Linda_us

#### Satisfied Customers:

3138
Post Graduate Diploma in Management (MBA)

### Chris M.

#### Satisfied Customers:

2602
Master's Degree, strong math and writing skills, experience in one-on-one tutoring (college English)

### F. Naz

#### Satisfied Customers:

2126
Experience with chartered accountancy

### Bizhelp

#### Satisfied Customers:

1887
Bachelors Degree and CPA with Accounting work experience

### Seanna

#### Satisfied Customers:

1781
3,000+ satisfied customers, all topics, A+ work