Question

resolva: 9x^2-1=3x - x^2

Answer 1

9x² - 1 = 3x - x²
9x² + x² - 3x - 1
10x² - 3x - 1 = 0

delta = b² - 4.a.c

a = 10
b = -3
c = -1

delta = (-3)² - 4.10.(-1)
delta = 9 + 40
delta = 49

x = -b ± √delta/2.a

x = -(-3) ± √49/2.10

x = 3 ± 7/20

x = 3 + 7/20 = 10/20 = 1/2

x = 3 - 7/20 = -4/20 = -1/5

s={ 1/2, -1/5}

☆Espero ter ajudado!