Question

Помогите сор по алгебре 7 класс 3 четверть 1 сор!! ​

Answer 1

Ответ:

1

$3 {x}^{4} - 75 = 3( {x}^{2} - 5)( {x}^{2} + 5)$

2

${53}^{2} - 26 times 53 + {13}^{2} = {(53 - 13)}^{2} = {40}^{2} = 1600$

3

${(2x + 3)}^{2} - (2x - 1)(2x + 1) = 46 \ 4 {x}^{2} + 12x + 9 - 4 {x}^{2} + 1 = 46 \ 12x + 10 = 46 \ 12x = 36 \ x = 3$

4

$(y - 5)(y + 2) - {(y - 7)}^{2} > 18 \ {y}^{2} + 2y - 5y - 10 - {y}^{2} + 14y - 49 > 18 \ 11y - 59 > 18 \ 11y > 77 \ y > 7$

5

$x - y = 5 \ {x}^{2} - {y}^{2} = 185 \ \ x = 5 + y \ {(5 + y)}^{2} - {y}^{2} = 185 \ 25 + 10y + {y}^{2} - {y}^{2} = 185 \ 10y = 160 \ y = 16 \ \ x = 16 + 5 = 21$