Помогите пжномер 31.3 первый столбик

1) a²- 49 = a² - 7² = (a-7) * (a+7)

3) c² - 2,25 = c² - $\frac{9}{4}$ = $\frac{1}{4} * (4c^{2} - 9) = \frac{1}{4} * (2c-3) * (2c + 3)$

5) $\frac{64}{81} - x^{2} = \frac{1}{81} * (64-81x^{2}) = \frac{1}{81} * (8-9x) * (8+9x)$

7) z² - $\frac{169}{196} = \frac{1}{196} * (196z^{2} - 169) = \frac{1}{196} * (14z - 13) * (14z+13)$

9) 25x² - 36 = 5²x² - 6² = (5x)² - 6² = (5x-6) * (5x+6)

11) 0, 64 - $\frac{1}{9} z^{2} = \frac{16}{25} - \frac{1}{9} z^{2}= \frac{1}{225}* (144 - 25z^{2} ) = \frac{1}{225} * (12-5z) * (12+5z)$