Question

Можете решить пожалуйста!

Answer 1

1. В

2. А

3. Г

4. Г

5. Б

$3x^{2} - 15 = 0 \\ x^{2} - 5 = 0 \\ x^{2} = 5 \\ x = + - \sqrt{5}$

6. Б

$2x^{2} + 7x = 0 \\ 2x(x + 3.5) = 0 \\ x = 0 \\ x = - 3.5 \\ 0 + ( - 3.5) = - 3.5$

7. В

$7 \times 8 = 56 \\ 56 - 8 = 48 \\ x {}^{2} - 7x = 0 \\ x(x - 7) = 0 \\ x = 0 \\ x = 7$

8. В

$(2x + 1)^{2} = 2x + 1 \\ 2x {}^{2} + 4x + 1 = 2x + 1 \\ 2 {x}^{2} + 2x = 0 \\ 2x(x + 1) = 0 \\ x = 0 \\ x = - 1 \\ 0 \times ( - 1) = 0$

9. В

$x {}^{2} (x - 5) {}^{2} - 5(x - 5) {}^{2} = 0 \\ x {}^{2} - 5 = 0 \\ (x - 5) {}^{2} = 0 \\ x = + - \sqrt{5} \\ x = 5$