<span>6x-5(2x+8)>14+2x</span>
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( z + v )/15 - ( z - v )/3 = 1
Z + v - 5( z - v ) = 15
z + v - 5z + 5v = 15
6v - 4z = 15
••••••••••••••
( 2z - v )/6 - ( 3z + 2v )/3 = - 25
2z - v - 2( 3z + 2v ) = - 25•6
2z - v - 6z - 4v = - 150
- 5v - 4z = - 150
•••••••
5v + 4z = 150
6v - 4z = 15
11v = 165
v = 15
6•15 - 4z = 15
4z = 90 - 15
z = 75 : 4
z = 18,75
Ответ
z = 18,75
v = 15
1)=0.25x2-0.5xy+0.5xy-y2=1/4x2-y2
2)=a6+a3b2-a3b2-b4=a6-b4
3)=16a+2ab+2ab+b2/4
4)=4a2/9+2ab-2ab-9b2=4a2/9-9b2
5)=(2x+y+z)*(2x-y-z)=4x2-2xy-2xz+2xy-y2-yz+2xz-yz-z2=4x2-y2-z2
6)=x2+xy+2xz+xy+y2+2yz-2xz-2yz-4z2=x2+2xy+4xz+y2-2yz-2xz-4z2=x2+y2-4z2+2xz+2xy-2yz