(14y+2)*(1,8-0,3y)=0

Question

(14y+2)*(1,8-0,3y)=0

Answer 1

(14y + 2) * (1,8 - 0,3y) = 0
25,2y - 4,2y^2 + 3,6 - 0.6y = 0
-4,2y^2 + 24,6y + 3,6 = 0 / *5 (домножаем на 5)
-21y^2 + 123y + 18 = 0
D = b^2 - 4ac = 15129+1512 =16641
√D = 129
y1 = -b+√D / 2a= 6 / 42 = 1/7
y2 = -b-√D / 2a= -252 / 42 = -6