Respuestas

2012-03-08T00:38:59+01:00

9 x 2 - 7x - 90 = 0

16 - 7x - 90 =  0

-7x = 0 + 90 - 16

-7x = 74 | :(-7)

x = - 74/7

x = - 10 4/7