Question

(2x-1)²-(x-1)(x+7)</=5 ​

Answer 1

2x-1)²-(x-1)(x+7)≤5
4x²-4x+1-(x²+7x-x-7)-5≤0
4x²-4x+1-x²-6x+7-5≤0
3x²-10x+3≤0
D=100-36=64
x1= (10+8)/6= 3
x2= (10-8)/6= 1/3
x∈[1/3;3]