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-5y + 20+y+5=-4y+25 все чітко і легко це множення многочленнів
<span>1)
2х²-5=0,
2х</span>² = 5,
<span>х</span>² = 2,5,
<span>х1 = </span>√2,5,
х2 = -√2,5,
<span>
2)
-х²+3=0,
х</span>² = 3,
<span>х1 = </span>√3,
<span>х2 = -</span>√3,
<span>
3)
-3(х+3)²+48=0,
-3(х+3)</span>² = -48,
<span>(х+3)</span>² = 16,
<span>х+3 = 16,
х = 16-3,
х1 = 13,
х+3 = -16,
х = -16-3,
х2 = -19,
4)
(х-4)</span>²<span>=1/4,
х-4 = </span>√1/4,
<span>х-4 = 1/2,
х1 = 4 1/2,
х-4 = -</span>√1/4,
<span>х-4 = -1/2,
х2 = 3 1/2,
5)
(х+1)²-4=0,
(х+1)</span>²<span> = 4,
х+1 = </span>√4,
х+1 = 2,
х1 = 1,
х+1 = -2,
х2 = -3
17 -(х+2)=13
17-х-2 =13
15-х =13
х=15-13
x=2
y-4,2+6,3y=9,3
7,3y-4,2 = 9,3
7,3y=9,3+4,2
7,3y =13,5
y=13,5 : 7,3
y=1,8