<span>(х+1)*(x²-10х+25) = 7(х-5),
(х+1)(х-5)</span>² = 7(х-5),
(x+1)*(x-5)²-7(x-5) = 0,
(x-5)*((x+1)*(x-5)-7) = 0,
x-5 = 0,
x₁ = 5,
(x+1)*(x-5)-7 = 0,
x²-5x+х-5-7 = 0,
x²-4x-12 = 0,
D = (-4)² - 4*1*(-12) = 16 + 48 = 64,
x₂ = (4 + 8)/2*1 = 12/2 = 6,
x₃ = (4 - 8)/2*1 = -4/2 = -2.
Ответ: x₁ = 5 x₂ = 6 x₃ = -2.
Решение во вложении...................................
1) 20,1 +а +(5,38+4,38)= 20,1+а+9,76= а+29,86
при а= 0, 098
0,098+29,86= 29,958
2) b+ 42.7 +(39.825-2.74) = b+ 42.7+37.085=b+79.785
при b=12.61
12.61+79.785= 92.325
3) 50.56 - (24.16+19.8)+c = 6.6+c
при с= 0.808
6,6+0,808= 7.408
4) d+ 60.19-(68.7-9.1) = d+0.59
d=21.012
21.012+0.59=21.602
1040:20*(140+76+260)-9908=52*(476)-9908=24752-9908=14844