Question

помогите пожалуйста

Answer 1

Ответ:

${x}^{2} - 9 = 0 \\ (x - 3)(x + 3) = 0 \\ 1)x - 3 = 0 \\ x = 3 \\ 2)x + 3 = 0 \\ x = - 3$

${x}^{2} - 6x = 0 \\ x(x - 6) = 0 \\ 1)x = 0 \\ 2)x - 6 = 0 \\ x = 6$

${(x - 5)}^{2} = 0 \\ x - 5 = 0 \\ x = 5\\ \\ \\ \\ {x}^{2} - 10x + 25 = 0 \\ d = {b}^{2} - 4ac = {( - 10)}^{2} - 4 \times 1 \times 25 = 100 - 100 = 0 \\ x = \frac{ - b}{2a} = \frac{ - ( - 10)}{2 \times 1} = \frac{10}{2} = 5$