Question

Найдите корни уравнений 4х^2-5х-9=0

Answer 1

$D=(-5)^2-4*4*(-9)=25+144=169=13^2 \x_1= frac{5+13}{8}=2,25 \x_2= frac{5-13}{8}=-1$
Ответ: x1=-1; x2=2,25

Answer 2

4х^2 - 5x - 9 = 0
D = 25 - 4*4*-9 = 25 + 144 = 169;   √D = 13
x1 = (5 + 13)/8 =18/8 = 2,25
x2 = (5 - 13)/8 = - 1