(30+12):3=42:3=14
(60+18):6=78:6=13
(40+18):2=58:2=29
1)8<span> x=38.9-6.1</span>
<span> 8 x=32.8</span>
<span>x=</span>4,1
2)<span>x =</span><span>75,6</span><span>/</span><span>14</span>
x=5,4
24+2x-x^2>x
24+2x-x^2-x>0
24+x-x^2>0
a=-1, b=1, c=24
D=b^2-4ac=1-4*(-1)*24=1+96=97
x1=(-b-D^1/2)/2a=(-1-97^1/2)/2*(-1)=(-10,85)/(-2)=5,425
x2=(-b+D^1/2)2a=(-1+97^1/2)2*(-1)=8,85/(-2)=-4,425
(D^1/2-это корень числа D в решении не писать)
1) 4 х 9 - 4 = 32
8 х 9 - 4 = 68
7 х 9 - 4 = 59
6 х 9 - 4 = 50
9 х 9 - 4 = 73
11 х 9 - 4 = 95
2) 5 + 4 = 9 : 9 = 1
14 + 4 = 18 : 9 = 2
23 + 4 = 27 : 9 = 3
41 + 4 = 45 : 9 = 5
86 + 4 = 90 : 9 = 10