Question

Explain why the dividing-out method is incorrect. You may want to start with a simpler expression and work your way up to polynomials. (For example, compare fraction numerator 3 left parenthesis 5 right parenthesis over denominator 3 end fraction and fraction numerator 3 plus 5 over denominator 3 end fraction.)
Explain when you can cancel a number that is in both the numerator and denominator and when you cannot cancel out numbers that appear in both the numerator and the denominator.
Share tricks, reminders, memory devices, or other methods to help students catch themselves before making this common mistake.
Post your video or series of images. Post answers to the following questions:

A. Why do you think the mistake shown here is such a common one?
B. Have you ever made this mistake before? What helped you stop making this mistake? What will help you stop making this mistake in the future?

Answer 1

For this exercise we must correct the error of the given fraction, differentiating the properties of addition and multiplication, so:

1)This error occurs frequently because when simplifying in a multiplication or division it cannot be done in the operations of subtraction and addition.

2)As this error is very common, it has probably already occurred. But one way to resolve this is to pay attention and redo the math.

to understand this error we have to:

$\frac{(3)(5)}{3} = 5$

In the case of multiplication the 3 of the numerator can be simplified with the 3 of the denominator, the other case will be:

$\frac{3+5}{3} = \frac{8}{5}$

In the case of addition or subtraction, you should always keep the denominator.

Learn more: brainly.com/question/1301963