835. Решите уравнение: a) (x-6)^2 - x(x + 8) = 2; б) 9x(x+6)-(3x + 1)^2 = 1; в) у(у - 1) - (у - 5)^2 = 2; г) 16у(2 - у) + (4y-5)^2=0.

a) (x-6)^2 - x(x+8) = 2 x^2 - 12x + 36 - x^2 - 8x = 2 -20x + 36 = 2 -20x = -34 x = 1.7 б) 9x(x+6)-(3x + 1)^2 = 1 9x^2 + 54x - (9x^2 + 6x + 1) = 1 48x - 1 = 1 48x = 2 x = 1/24 в) у(у - 1) - (у - 5)^2 = 2 y^2 - y - (y^2 - 10y + 25) = 2 9y - 25 = 2 9y = 27 y = 3 г) 16у(2 - у) + (4y-5)^2=0 32y - 16y^2 + 16y^2 - 40y + 25 = 0 -8y + 25 = 0 8y = 25 y = 25/8 = 3.125