Question

x² = x + 12 (R: -3,4)​

Answer 1

Bom dia!

x² = x + 12

x²-x-12 = 0

a = 1

b= -1

c = -12

∆ = b²-4.a.c

∆= (-1)² - 4 .1.(-12)

∆ = 1 + 48

∆= 49

x = -b±√∆/2.a

x= -(-1) ±√49/2

x'= 1 + 7 /2

x' = 8/2

x' = 4

x" = 1 -7/2

x"= -6/3

x"= -3

S = { -3,4}

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