Question

RESOLVA AS EQUAÇÕES DO 2 GRAU EM IR:
 
a) x²-81=0
 
b)3x²-10=0
 
c)9x-4=0
 
d)3x²-6x=0
 

Answer 1

a)$x^{2} - 81 = \\ x^{2} =81 \\ x = \sqrt{81} \\ x = 9$

b) $3 x^{2} - 10 = 0 \\ 3 x^{2} = 10 \\ x^{2} = \frac{10}{3} \\ x = \sqrt{10/3}$

c) $9x - 4 = 0 \\ 9x = 4 \\ x = \frac{9}{4}$

d) $3 x^{2} - 6x = 0 \\ 3 x^{2} = 6x \\ x^{2} = \frac{6x}{3} \\ x^{2} = 2x \\ x = \sqrt{2x}$