Discover a wealth of knowledge and get your questions answered at IDNLearn.com. Whether your question is simple or complex, our community is here to provide detailed and trustworthy answers quickly and effectively.
Sagot :
[tex]9{ x }^{ 2 }-25\\ \\ ={ 3 }^{ 2 }{ x }^{ 2 }-{ 5 }^{ 2 }\\ \\ ={ \left( 3x \right) }^{ 2 }-{ 5 }^{ 2 }\\ \\ =\left( 3x+5 \right) \left( 3x-5 \right) [/tex]
Here's a rule that I learned from my algebra teacher almost 60 years ago.
It's so handy, and I use it so often, that it's still fresh in my mind, and even
though it's so old, it still works !
In fact, it's so useful that it would be a great item for you to memorize
and keep in your math tool-box.
==> To factor the difference of two squares, write
(the sum of their square roots) times (the difference of their square roots) .
That's exactly what you need to solve this problem.
I'll show you how it works:
9x² - 25
You look at this for a few seconds, and you realize that
9x² is the square of 3x , and 25 is the square of 5 .
So this expression is the difference of two squares,
and you can use the shiny new tool I just handed you.
The square roots are 3x and 5 .
So the factored form of the polynomial is (3x + 5) (3x - 5) .
That's all there is to it. If you FOIL these factors out, you'll see
that you wind up with the original polynomial in the question.
Thank you for joining our conversation. Don't hesitate to return anytime to find answers to your questions. Let's continue sharing knowledge and experiences! Your questions find clarity at IDNLearn.com. Thanks for stopping by, and come back for more dependable solutions.