0,64x^2+1,6x+1=0 помогите

Question

0,64x^2+1,6x+1=0 помогите

Answer 1

0,64x^2 + 1,6x + 1 = 0   
16x^2  + 40x + 25 = 0 
D = 1600 - 1600 = 0 
x1, 2 = - b/2a = - 40/(2*16) = - 5/4 = - 1,25

Comments

спасибо!