<em />5ab+10a2=5a*(b+2a)
6x2-3x3-9x4=3x2*(2-x-3x2)
6c2x3-4c3x2+2c2x2=2c2x2*(3x-2c)
Уравнения: 2x2+4x=0 3x-5x2=0
x*(2x+4)=0 x*(3-5x)=0
x=0 2x+4=0 x=0 3-5x=0
2x=-4 3=5x
x=-2 x=3/5
Пропорция
800 100\%
Х 85\%
Х=(800*85)/100=680
800-680=120
X + y = 750
0.8x + 1.2y = 660
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x + y = 750
2x + 3y = 1650
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2x + 2y = 1500
2x + 3y = 1650
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y = 150
x = 750 - 150 = 600