Question

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1)(12a-3b+10)-(4a+5b-20)=
2)-(4a2+2a)-(3a-5a2+8)=
3)7x-(y-2z+x)-(5y+3z)(3x-4y)=
4)5a-(2-x)+b-2x+5=
5)2a (b-3)-2b (a-3)=
6)5a (a-2)+2a (a+5)=
7)3 (a+2b-3c)-2 (a+2c)+5 (c-b) - (a+b)=
8)2 (a+2x) - (a-3x-1)+3 (a-4x)=
9)-3,2x+(-0,8y+2z)-(1,2y-0,8x)-(2z-2,4x)=

Answer 1

1)(12a-3b+10)-(4a+5b-20)=

=12a - 3b + 10 - 4a - 5b + 20 = 8a - 8b + 30

2)-(4a²+2a)-(3a-5a²+8)=

= - 4a² - 2a - 3a + 5a² - 8 = 

= a² -5a - 8

3)7x-(y-2z+x)-(5y+3z)(3x-4y)=

=7x - y + 2z - x - (15xy - 20y² +9z² -12yz)

= 6x - y + 2z - 15xy + 20y² - 9z² + 12yz=

=20y² - 9z² + 6x - y + 2z - 15xy + 12yz

4)5a-(2-x)+b-2x+5=

= 5a - 2 +x + b - 2x +5 =

= 5a - x + b + 3

5)2a (b-3)-2b (a-3)=

= 2ab - 6a - 2ab + 6a=

=0

6)5a (a-2)+2a (a+5)=

= 5a² - 10a + 2a² + 10a

=7a²

7)3 (a+2b-3c)-2 (a+2c)+5 (c-b) - (a+b)=

= 3a + 6b - 9c - 2a - 4c + 5c  - 5b - a - b =

=-8c

 

8)2 (a+2x) - (a-3x-1)+3 (a-4x)=

= 2a + 4x - a + 3x + 1 + 3a - 12x=

=4a - 5x +1

9)-3,2x+(-0,8y+2z)-(1,2y-0,8x)-(2z-2,4x)=

= -3,2x - 0,8y - 2z - 1,2y +0,8x - 2z + 2,4x=

=-2y -4z