Решение:
- a) √x² - 297 = 12
\( x^2 - 297 = 12^2 \)
\( x^2 - 297 = 144 \)
\( x^2 = 144 + 297 \)
\( x^2 = 441 \)
\( x = \pm \sqrt{441} \)
\( x = \pm 21 \) - б) √x² + 184 = 25
\( x^2 + 184 = 25^2 \)
\( x^2 + 184 = 625 \)
\( x^2 = 625 - 184 \)
\( x^2 = 441 \)
\( x = \pm \sqrt{441} \)
\( x = \pm 21 \) - в) √x² + 25 = 13
\( x^2 + 25 = 13^2 \)
\( x^2 + 25 = 169 \)
\( x^2 = 169 - 25 \)
\( x^2 = 144 \)
\( x = \pm \sqrt{144} \)
\( x = \pm 12 \) - г) √4x + 20 = 10
\( 4x + 20 = 10^2 \)
\( 4x + 20 = 100 \)
\( 4x = 100 - 20 \)
\( 4x = 80 \)
\( x = \frac{80}{4} \)
\( x = 20 \)
Ответ: а) ±21; б) ±21; в) ±12; г) 20.