Answer:

1.17a+19b

2.-c-d

3.12x+10−8

4.-2x+7−10

5.2x²+9x−9

Step-by-step explanation:

1.Remove parentheses.9a+5b+2a+2b+6a+12b

Collect like terms.

(9a+2a+6a)+(5b+2b+12b)

Simplify.

17a+19b

2.Remove parentheses.

-8c+d+7c-2d

Collect like terms.

(-8c+7c)+(d-2d)

Simplify.

-c-d

3.Eliminate redundant parentheses

(4x +7y - 9) + (8x + 3y + 1)

4x +7y - 9) + (8x + 3y + 1

Add the numbers

4x+7−9+8x+3+1

4x+7−8+8x+3

Combine like terms

4x+7−8+8x+3

12x+7−8+3

Combine like terms

12x+7−8+3

12x+10−8

solution

12x+10−8

4.Distribute

( 5 + 9 − 7 ) − ( 7 + 2 + 3 )

(5x+9y-7)-7 + 2 + 3

Eliminate redundant parentheses

( 5 + 9 − 7 ) −7x−2y−3

5+9−7−7−2−3

Subtract the numbers

5 + 9 − 7 − 7 − 2 − 3

5x+9−10−7−2

Combine like terms

5x+9−10−7−2

-2x+9−10−7−2

Combine like terms

-2x+9−10−7−2

-2x+7−10

Solution

-2x+7−10

5.Remove parentheses.

3x² + 4x - 2) - (x² - 5x + 7

Collect like terms.

(3x²−x²)+(4x+5x)+(−2−7)

Simplify.

2x²+9x−9