Question

CALCULE:

A:(a²-2ab)+(5ab-3a²)


B:(5a-2b)-(2c-3a+b)


C:(4a²-8a+6)-(2a+5a²-2)


D:(3x²-5x+2)-(x²+6x-4)+(5x-7)


E:(a²-ab)+(b²-ab)-(a²+b²)




POR FAVOR!

Answer 1

( a² - 2ab) + (5ab - 3a²) =
a² - 2ab + 5ab - 3a² =
a² - 3a² - 2ab + 5ab = 
- 2a² + 3ab
-----------------------------------------------------

( 5a - 2b) - ( 2c - 3a + b) =
5a - 2b - 2c +  3a - b =
5a + 3a - 2b - b - c =
8a - 3b - c
------------------------------------------------------------------------

( 4a² - 8a + 6) - ( 2a + 5a² - 2) =
4a² - 8a + 6 - 2a - 5a² + 2 =
4a² - 5a² - 8a - 2a + 6 + 2 =
- a² - 10a + 8
------------------------------------------------------

( 3x² - 5x + 2) - (x² + 6x - 4) + ( 5x - 7) =
3x² - 5x + 2 - x² - 6x + 4 + 5x - 7 =
3x² - x² - 5x + 5x - 6x + 2 + 4 - 7 = 
2x² - 6x - 1
--------------------------------------------------------------

(a² - ab) + ( b² - ab) - (a² + b²) =
a² - ab + b² - ab - a² - b² =
a² - a² - ab - ab + b² - b² = - 2ab