Resposta:
Explicação passo-a-passo:[tex]12x^{2} - 30x = 0\\\\\\\\x (12x - 30) = 0 \\\\x = 0\\\\ \\12x - 30 = 0\\x = 30/12 \\x = 2,5 \\\\S {0; 2,5}[/tex]
12x² - 30x = 0
0 = x (12x - 30)
12x - 30 = 0
12x = 30
x = 30/12
x = 5/2
