Пж помогите 8 класссс

Здравствуйте!

Вот ваше решение:

$6x^{2}- 18 = 0 \\x^{2}- 3 = 0\\x^{2} = 3\\x= -\sqrt{3}\\x= \sqrt{3} \\x_{1}= -\sqrt{3} \\x_{2} = \sqrt{3} \\\\y^{2}- 5y = 0\\y *(y-5) = 0\\y = 0\\y - 5 = 0\\y = 0\\y = 5\\y_{1} = 0\\y_{2} = 5 \\\\x^{2}-6x + 5 = 0\\ x^{2} -x -5x +5 = 0\\x*(x-1)-5(x-1)=0\\(x-1)*(x-5)= 0\\x-1 = 0\\x-5=0 \\x=1\\x= 5\\x_{1}= 1\\x_{2} = 5\\\\10x^{2} -3x - 0.4 = 0\\50x^{2} -15x -2 = 0\\50x^{2} + 5x - 20x - 2 = 0\\5x*(10x+1) - 2(10x+1) = 0\\(10x+1)*(5x-2)=0\\10x + 1 = 0\\ 5x - 2 = 0\\ x = -\frac{1}{10}\\ x= \frac{2}{5}$