(×-3)(2×+10)=(×+2)^2 решите уравнение
2x^2 + 10x - 6x - 30 = x^2 - 4x + 4 x^2 + 8x - 34 = 0 D= 64 + 156 = 220 x1= (-8 + √220)/2 x2= (-8-√220)/2