Question

Пожалуйста помогите) мне

Answer 1

1)

$-5x^2+3x+2=0\\5x^2-3x-2=0\\x1 = \frac{3+\sqrt{9+40}}{10} = 1\\x2 = \frac{3-\sqrt{9+40}}{10} = -0.4$

2)

$9-6x+x^2=0\\x^2-6x+9=0\\x = \frac{-6+\sqrt{36-36}}{2} = -3$

3)

$4x^2+5x+1=0\\x1 = \frac{-5+\sqrt{25-16}}{8} = -0.25\\x2 = \frac{-5-\sqrt{25-16}}{8} = -1$

4)

$7x^2+21x-28=0\\x1 = \frac{-21+\sqrt{441+784}}{14} = 1\\x2 = \frac{-21-\sqrt{441+784}}{14} = -4$

5)

$3x^2-24x+45=0\\x1 = \frac{24+\sqrt{576-540}}{6} = 5\\x2 = \frac{24-\sqrt{576-540}}{6} = 3$