ДАЮ 20 БАЛЛОВ!!!!!! -0.7x(0.6x+0.4)+0.3(0.6x+0.4)=0

Question

ДАЮ 20 БАЛЛОВ!!!!!!
-0.7x(0.6x+0.4)+0.3(0.6x+0.4)=0

Answer 1

-0,7х(0,6х+0,4)+0,3(0,6х+0,4)=0
-0,42х2-0,28+0,18х+0,12=0
-0,24х=-0,16
х=(-0,24)/(-0,16)
х=1,5

Answer 2

....................................

---