Question

2x² - 98 = 0 quais sao as raizes da equaçao ?

Answer 1

2x²-98=0
2x²=98
x²=98/2
x²= 49
x= √49
x= +7, -7

S:[+7,-7]

Answer 2

2x² - 98 = 0 

a = 2 , b = 0 , c = -98 

Δ = b² - 4ac
Δ = 0² - 4.2.(-98)
Δ = 0 - (-784)
Δ = 784

x = - b ± √Δ
          2a

x = - 0 ± √784
           2.2

x = - 0 ± 28
          4

x' = - 0 + 28 = 28 = 7
           4         4

x" = - 0 - 28 = - 28 = -7
           4           4

S = { -7 , 7 } 

as raizes são - 7 e 7