1)у=4-2,5x x=1;2
y=4-2,5×1=1,5
y=4-2,5×2=4-5=-1
2)1,75x+y=3
y= 3-1,75x x=2; 3
y=3 -1,75×2= 3-3=0
y=3-1,75×3= 3-5,25=-2,25
3) 3x+y=0
y=0-3x
y=-3x x=1;2
y=-3×1= -3
y=-3×2
y=-6
V=πR^2
V=3,14*4^2
V=3,14*16
V=50,24 дм^3
Ответ:V=50,24 дм^3
<span>10/x − 3/x+21 =0
7/х+21=0
7/х=-21
х=7:(-21)
х=-7/21
х=-1/3
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