Last visit was: 22 Apr 2026, 19:19 It is currently 22 Apr 2026, 19:19
Close
GMAT Club Daily Prep
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.
Close
Request Expert Reply
Confirm Cancel
User avatar
zepster313
Joined: 24 Oct 2024
Last visit: 22 Nov 2024
Posts: 9
Posts: 9
Kudos: 0
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 22 Apr 2026
Posts: 109,754
Own Kudos:
Given Kudos: 105,823
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,754
Kudos: 810,672
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
zepster313
Joined: 24 Oct 2024
Last visit: 22 Nov 2024
Posts: 9
Posts: 9
Kudos: 0
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 22 Apr 2026
Posts: 109,754
Own Kudos:
Given Kudos: 105,823
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,754
Kudos: 810,672
Kudos
Add Kudos
Bookmarks
Bookmark this Post
zepster313
Bunuel
zepster313
I seem to get lost trying to factor equations. During the test calculators aren't allowed so using the quadratic formula seems a bit wasteful of time.
I have a doubt from the official quantitative guide that I wanted to clear

Problem. In this problem, how do they go from \(x(x-1)^2+5(x-1)^2\) to \((x+5)(x-1)^2\) in one step?

My work. Here I would try to do it the long way but I would get stuck on the last step with the red underline where I don't know how to factor a polynomial of the third degree.


Additionally, how can I quickly factor \(x^2-2x+1\) or any polynomial of the second degree without having to use the quadratic formula. I know this one is a bit easier but what about \(2x^2+6x-42\) for example? How would I quickly factor that to get both solutions of x?

1. How they go from \(x(x-1)^2 + 5(x-1)^2\) to \((x+5)(x-1)^2\):

In the expression \(x(x-1)^2 + 5(x-1)^2\), both terms contain \((x-1)^2\) as a common factor. So, you can factor out \((x-1)^2\) from each term:

\(x(x-1)^2 + 5(x-1)^2 = (x-1)^2 (x+5)\)

This is a straightforward factorization using the distributive property, where (x-1)^2 is factored out, leaving x + 5 in the parentheses.
I still don't quite understand what you mean by factor out. Wouldn't removing the \((x-1)^2\) from each term make it just x+5 since you're removing the \((x-1)^2\) from both terms?

When we say "factor out," we mean to treat (x-1)^2 as a common factor and place it outside the parentheses, just like you would with any other term that appears in multiple parts of an expression.

In this case:

\(x(x-1)^2 + 5(x-1)^2\)

becomes:

\((x-1)^2 * (x + 5)\)

This step does not "remove" (x-1)^2; instead, it pulls (x-1)^2 out as a common factor in front, leaving (x + 5) inside the parentheses. It’s like saying:

\(a * b + c * b = b * (a + c)\)

where b is the common factor. Here, (x-1)^2 is the common factor, and (x + 5) remains after factoring.

You might want to review some algebra fundamentals. Here’s a helpful link to get started with Algebra 101
Moderators:
Math Expert
109754 posts
Tuck School Moderator
853 posts