Решение на фото вроде так
1
(2х-4)(3х+12) = 0
6х<span>²+24х-12х-48=0
6х</span><span>²+12х-48=0
х</span><span>²+2х-8 = 0
D = 2</span><span>²-4*1*(-8)
D = 4+32 = 36
х1 = (-2+6):2 = 4:2 = 2
х2 = (-2-6):2 = -8:2 = -4
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2
x</span><span>²-12x+45 = (x-15)(x+3)
1). (x-15)(x+3) = x</span>²+3x-15х-45 = х<span>²-12х-45
2). </span>х²-12х-45 = х<span>²-12х-45</span>
А) 13>-6
б) -4 3/7 < 0
-31+4
--------- < 4/7
7
27/7 < 4/7
3 6/7 < 4/7
X=8+2y
(8+2y)²+2y²-22=0
x=8+2y
64+32y+4y²+2у²-22=0
x=8+2y
6y²+32у+42=0
x=8+2y
3у²+16у+21=0
Д=256-252=4=2²
у1=(-16+2)/6=-7/3
у2=(-16-2)/6=-3
х1=10/3
х2=2