Алгебра 133)1,2,3,4 134)2.4.5 135)1,2 Заранее большое спасибо
355 1) 1.3x+0.2=0.7x^2 13/10x+1/5=7/10x^2 13X+2=7x^2 13x+2-7x^=0 -7x^2+13x+2=0 7x^2-13x-2=0 Д=169-4*7*(-2)=169+56=225=15 Х1=13+15/14=2 Х2=13-15/14=-1/7 2)0,09-4X^2 9/100-4x^2=8/5x 9-400x^2=160x 9-400x^2=160x=0 -400x^2-160X+9=0 400x^2-160X-9=0 400x^2-160X+9=0 д=25600-4*4000*(-9)=25600+14400=40000=200 x1=-160+200/800=-9/20 x2=-160-200/800=1/20