Question

resolva as equaçoes 1)x²-4=0 2)x²-2x1-3=0

Answer 1

1) x² = 4
    x² = 2 ² 
    x = 2

2) x² - 2x - 3 = 0
    
a = 1
b = -2
c = -3

delta = b² - 4ac
delta = (-2²) - 4.1.(-3)
delta = 4 + 12
delta = 16

x = -b +- raiz delta / 2a
x = 2 +- raiz 16 / 2.1
x = 2 +- 4 / 2

x' =(2 + 4) / 2 = 6/2 = 3
x'' = (2-4) / 2 = -2/2 = -1

x = -1 ou x=3

Answer 2

1)x^{2}-4=0
    x=raiz de4