Question

Поогите решить уравнения .
(Х:2-1,6)*(5х+1)=0

Answer 1

(x:2-8:5)*(5x-1)=0
x:2-8:5=0
5x-1=0
5x=1
x=1:5=0.5
x=16:5=3.2

Answer 2

5x²/2-15x/2-1.6=0
2.5x²-7.5x-1.6=0
D=-7.5²-4*2.5*(-1.6)=72.25
x1=(√72.25-(-7.5))/(2*2.5)=3.2
x2=(-√72.25-(-7.5))/(2*2.5)=-0.2