Please help need help with this question

Which value is not a solution of 8x^3 – 1 = 0

Which equation shows the quadratic formula used correctly to solve 5x2 + 3x -4 0 for x? cos -3+ v (3) 2-4() 2(5) 3+ |(3)² +4() 205) 3+ (3) 2-4() -3+ v (3)² +4()

Pls never taught i’m really confused and i rlly need