Ответы и объяснения

2013-05-17T16:36:53+00:00

= 4х^2 + 12x-27=0

 D = 144- 4*4*( - 27) = 576 

x1 = 1.5

x2 = - 4.5

 

2013-05-17T20:26:39+00:00

3x^2-10x+30=7x^2+2x+3

-4x^2-12x+27=0

D=(-12)^2-4*(-4)*27=144+432=576

x1=(24-(-12))/(2*(-4))=-36/8=-4.5
x2=(-24-(-12))/(2*(-4))=1.5