Question

x ^ 2 + x = 0

10x - 42x ^ 2 = 0

14x^ 2 =7x;


2x * (3 - 6x) = 0

4x ^ 2 - 13x = 0 ;

2x ^ 2 + 21x = 0 ;

18. 3x - 21x ^ 2 = 0 ;
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Answer 1

Ответ:

Объяснение:

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

$10x - 42 {x}^{2} = 0 \\ 2x(5 - 21x) = 0 \\ 2 x= 0 \\ 5 - 21x = 0 \\ x = 0 \\ 21x = 5 \\ x = 0 \\ x = \frac{5}{21}$

$14 {x}^{2} = 7x \\ 14 {x}^{2} - 7x = 0 \\ 7x(2x - 1) = 0 \\ 7x = 0 \\ 2x - 1 = 0 \\ x = 0 \\ 2x = 1 \\ x = 0 \\ x = \frac{1}{2}$

$2x(3 - 6x) = 0 \\ 6x - 12 {x}^{2} = 0 \\ 6x(1 - 2x) = 0 \\ 6x = 0 \\ 1 - 2x = 0 \\ x = 0 \\ 2x = 1 \\ x = 0 \\ x = \frac{1}{2}$

$4 {x}^{2} - 13x = 0 \\ x(4x - 13) = 0 \\ x = 0 \\ 4x - 13 = 0 \\ x = 0 \\ 4x = 13 \\ x = 0 \\ x = \frac{13}{4} = 3 \frac{1}{4}$

$2 {x}^{2} + 21x = 0 \\ x(2x + 21) =0 \\ x = 0 \\ 2x + 21 = 0 \\ x = 0 \\ 2x = - 21 \\ x = 0 \\ x = \frac{ - 21}{2} = - 10 \frac{1}{2}$

$3x - 21 {x}^{2} = 0 \\ 3x(1 - 7x) = 0 \\ 3x = 0 \\ 1 - 7x = 0 \\ x = 0 \\ 7x = 1 \\ x = 0 \\ x = \frac{1}{7}$