Question

Me ajudem 4x²-28x+40=0

Answer 1

Vamos lá: 4x^2 - 28x + 40 = 0 (÷4) x^2 - 7x + 10 = 0 Fórmula de Bhaskara: x^2 - 7x + 10 = 0 a = 1 b = -7 c = 10 ∆ = b^2 - 4ac ∆ = (-7)^2 - 4.1.10 ∆ = 49 - 40 ∆ = 9 x = (-b +-√∆)/2a x = (7 +-√9)/2 x = (7 +- 3)/2 x' = (7 + 3)/2 x' = 10/2 x' = 5 x'' = (7 - 3)/2 x'' = 4/2 x'' = 2 S = {2, 5}