Question

Resolva as equações do 2º grau encontrando suas raízes.
a) x² - 121 = 0

b) 2x² - 32 = 0

c) 5x² - 50 = 0

d) x² + 5x = 0

e) 7x²= 0

f) x²+ 25 = 0

g) 3x² - 3x = 0 ​

Answer 1

Resposta:

a) x^2-121=0 -> x^2=121 -> x=$\sqrt{121}$ -> x=11

b) 2x^2-32=0 -> 2x^2=32 -> x^2=32/2 -> x^2=16 -> x=$\sqrt{16}$ -> x=4

c) 5x^2-50=0 -> 5x^2=50 -> x^2=50/5 -> x^2=10 -> x=$\sqrt{10}$ -> x= 3,16

d) x^2+5x=0 -> x(x+5)=0 -> x=0 ; x+5=0 -> x= -5

e) 7x^2=0 -> x^2=0/7 -> x=0

f) x^2+25=0 -> x^2= -25 -> x= $\sqrt{-25}$

g) 3x^2-3x=0 -> x(3x-3)=0 -> x=0; 3x-3=0 -> 3x=3 -> x=3/3 -> x=1