Решите неравенство(x+3)^2-2x(x-4)< =49 .

(x+3)^2-2x(x-4)<=49
x²+6x+9-2x²+8x-49≤0
-x²+14x-40≤0
x²-14x+40≥0
x²-10x-4x+40≥0
x(x-10)-4(x-10)≥0
(x-10)(x-4)≥0

[4][10]

x∈(-∞;4]U[10;+∞)