Vamos là.
a)
x² + 3x*(x - 12) = 0
x² + 3x² - 36x = 0
4x² - 36x = 0
x*(4x - 36) = 0
x1 = 0
4x2 = 36
x2 = 9
b)
(x - 5)² = 25 - 9x
x² - 10x + 25 = 25 - 9x
x² - x = 0
x*(x - 1) = 0
x1 = 0
x2 = 1
c)
(x - 4)² + 5x*(x - 1) = 16
x² - 8x + 16 + 5x² - 5x = 16
6x² - 13x = 0
x"(6x - 13) = 0
x1 = 0
x2 = 13/6
d)
11x²/10 - 3x/5 - x/2 = 0
11x² - 6x - 5x = 0
11x² - 11x = 0
x² - x = 0
x*(x - 1) =0
x1 = 0
x2 = 1
