Question

$5 - 0.4x {}^{2} = 2$
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Answer 1

Ответ:

Решение на фото...................

Answer 2

$5 - 0.4x {}^{2} = 2 \\0.4 {x}^{2} = 2 + 5 \\ 0.4 {x}^{2} = 7 \\ {x}^{2} = 17.5 \\ x = \sqrt{17.5}$