Respuestas

2013-02-10T13:43:21+01:00

x3 -5x²-9x+20

 

x=1

1-5(1)-9(1)+20= 1-5-9+20=7

x=2

8-5(4)-9(2)+20= 8-20-18+20= -10

x=4

64 -5(16)-9(4) +20 = 64-80-36+20= -32