Question

Equações de 2 grau A)x² 7x=0 B)x²+5x=0 C)4x²-9x=0

Answer 1

x² - 7x = 0
x(x - 7) = 0
x = 0
ou 
x - 7 = 0
x = 7

Resp.: x = 0 e x = 7
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x² + 5x = 0
x(x + 5) = 0
x = 0

x + 5 = 0
x = - 5

R.: x = 0 e x = - 5
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c)
4x² - 9x = 0
x(4x - 9) = 0
x = 0

4x - 9 = 0
4x = 9
x = 9/4

R.: x = 0 e x = 9/4