Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized for You

we will pick new questions that match your level based on your Timer History

Track Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

p and m are positive integers, and p is a prime number. If x^2-mx+p=0 has a positive interger solution what is the value of (m-p)?

Thanks in advance !!

In any quadratic equation \(ax^2 + bx + c = 0\), the relationship between b and c is that b is the sum of the factors of c*a.

In \(x^2 - mx + p = 0\), we know -m is the sum of the factors of p, and we also know that p is the prime number that means it has only two factors, p and 1

Re: p and m are positive integers, and p is a prime number. If x [#permalink]

Show Tags

03 Jul 2014, 05:19

Narenn wrote:

alokgupta1009 wrote:

Hi,

Need your guidance for below qq.

p and m are positive integers, and p is a prime number. If x^2-mx+p=0 has a positive interger solution what is the value of (m-p)?

Thanks in advance !!

In any quadratic equation \(ax^2 + bx + c = 0\), the relationship between b and c is that b is the sum of the factors of c*a.

In \(x^2 - mx + p = 0\), we know -m is the sum of the factors of p, and we also know that p is the prime number that means it has only two factors, p and 1

So -m = -p -1 -------> m - p = 1

Hope that helps

I didn't understand the explanation. Could you elaborate and give a numerical example?

p and m are positive integers, and p is a prime number. If x^2-mx+p=0 has a positive interger solution what is the value of (m-p)?

Thanks in advance !!

In any quadratic equation \(ax^2 + bx + c = 0\), the relationship between b and c is that b is the sum of the factors of c*a.

In \(x^2 - mx + p = 0\), we know -m is the sum of the factors of p, and we also know that p is the prime number that means it has only two factors, p and 1

So -m = -p -1 -------> m - p = 1

Hope that helps

I didn't understand the explanation. Could you elaborate and give a numerical example?

In quadratic equation \(x^2 + bx + c = 0\), -b is the sum of the factors and c is the product. Suppose the factors of the equation are p and q then we can express \(x^2 + bx + c = 0\) as \(x^2 + (p+q)x + pq = 0\) where pq = c and p+q = -b Consider the equation \(x^2 - 5x + 4 = 0\) The factors of this equation are 4 & 1 so this equation can be expressed as \(x^2 - (4+1)x + (4*1) = 0\)

In the equation \(x^2 - mx + p = 0\) we know that P is the prime number, so it can have only two factors: p and 1, so we can express the equation as \(x^2 - (p+1)x + (p*1) = 0\). SO we have that -m = -p -1 and P = p ------> so m - p = p + 1 - p -----> 1

p and m are positive integers, and p is a prime number. If x [#permalink]

Show Tags

05 Jul 2014, 02:10

Hi Narren,

Why you did not consider:-p+1=-m Along with -p-1=-m I think above mentioned relation is also valid because m is sum or difference of factors.

Then -1 is also a possible value.
_________________

Piyush K ----------------------- Our greatest weakness lies in giving up. The most certain way to succeed is to try just one more time. ― Thomas A. Edison Don't forget to press--> Kudos My Articles: 1. WOULD: when to use?| 2. All GMATPrep RCs (New) Tip: Before exam a week earlier don't forget to exhaust all gmatprep problems specially for "sentence correction".

Version 8.1 of the WordPress for Android app is now available, with some great enhancements to publishing: background media uploading. Adding images to a post or page? Now...

“Keep your head down, and work hard. Don’t attract any attention. You should be grateful to be here.” Why do we keep quiet? Being an immigrant is a constant...

“Keep your head down, and work hard. Don’t attract any attention. You should be grateful to be here.” Why do we keep quiet? Being an immigrant is a constant...