the problem is about adding and subtracting polynomials...

This is what I did...

2x+3+3x+1
=2x+3x+3+1
=5x+4

and

9x+11-5x+4
=9x-5x+11+4
=4x+15

but then, if I add both 5x+4+4x+15
=9x+19...

I think this deals with the same problem you posted at 8:49 pm

In this question I think you wanted to subract 5x+4 from 9x+11

that would be 9x+11 - (5x+4)
= 9x + 11 - 5x - 4
= 4x + 7

See how important brackets and the order of operations are ??

(9m + 6) + (-5m - 6)

= (9m - 5m) + (6 - 6)

= 4m + 0
= 4m

(3r² + 7r + 1) + (4r² - 8r - 2)

(3r² + 7r + 1) + (4r² - 8r - 2)

= 3r² + 4r² + 7r - 8r + 1 - 2 (grouping like terms)

= 7r² - r - 1

(6h + 1) - (9h + 4)

(6h + 1) - (9h + 4)

= 6h + 1 - 9h - 4 (distribute the negative sign to all terms inside the parentheses)

= -3h - 3

(-7w² - 2w - 1) - (-5w² + 3w - 2)

(-7w² - 2w - 1) - (-5w² + 3w - 2)

= -7w² - 2w - 1 + 5w² - 3w + 2 (change the signs inside the second set of parentheses and combine like terms)

= -2w² - 5w + 1

It seems like you made a mistake when adding the two polynomials. Let me walk you through the correct steps for adding and subtracting polynomials.

To add or subtract polynomials, you need to combine like terms. Like terms are terms that have the same variables raised to the same powers.

Let's start with the first expression: 2x+3+3x+1.

1. Group the like terms together: (2x + 3x) + (3 + 1).
- The terms 2x and 3x are like terms because they both have the variable x raised to the power of 1.
- The terms 3 and 1 are constants and can be grouped together.

2. Combine the like terms: 5x + 4.

Now, let's move on to the second expression: 9x+11-5x+4.

1. Group the like terms together: (9x - 5x) + (11 + 4).
- The terms 9x and -5x are like terms because they both have the variable x raised to the power of 1.
- The terms 11 and 4 are constants and can be grouped together.

2. Combine the like terms: 4x + 15.

If we want to add (5x + 4) and (4x + 15):

1. Group the like terms together: (5x + 4x) + (4 + 15).
- The terms 5x and 4x are like terms because they both have the variable x raised to the power of 1.
- The terms 4 and 15 are constants and can be grouped together.

2. Combine the like terms: 9x + 19.

Therefore, the correct result of adding (5x + 4) and (4x + 15) is 9x + 19.