Question

x = -b +√b²-4.a.c sendo A=2,b=5e c=2,o valor 2.a

Answer 1

Δ = b² - 4ac
Δ = 5² - 4. 2 . 2
Δ = 25 - 16
Δ = 9

x = (-b +- √Δ)/2a
x = (-5 +- √9)/2.2
x = (-5 +- 3)/4

x'  = (- 5 + 3)/4 = -2/4 = -1/2
x' = (- 5 - 3)/4 = -8/4 = -2

=)