Question

${x}^{2} = x + 12$
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Answer 1

Resposta:

x' = 4

x" = - 3

Explicação passo-a-passo:

x^2 = x + 12

x^2 - x - 12 = 0

a= 1; b = - 1; c = - 12

∆ = b^2 - 4ac

∆ = (-1)^2 - 4.1.(-12)

∆ = 1 + 48

∆ = 49

x = [ - b +/- √∆]/2a

x = [ -(-1) +/- √49]/2.1

x = [ 1 +/- 7]/2

x' = [1 + 7]/2 = 8/2 = 4

x" = [ 1 - 7]/2 = - 6/2 = - 3

R.:

x = 4; x = - 3