\[\boxed{\text{22\ (22).\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
Пояснение.
Решение.
\[\textbf{а)}\text{\ x}^{2} - 25 = x^{2} - 5^{2} =\]
\[= (x - 5) \cdot (x + 5)\]
\[\textbf{б)}\ 16 - c^{2} = 4^{2} - c^{2} =\]
\[= (4 - c) \cdot (4 + c)\]
\[\textbf{в)}\ a^{2} - 6a + 9 =\]
\[= a^{2} - 2 \cdot 3 \cdot a + 3^{2} = {(a - 3)}^{2}\]
\[\textbf{г)}\ x^{2} + 8x + 16 =\]
\[= x^{2} + 2 \cdot 4 \cdot x + 4^{2} = {(x + 4)}^{2}\]
\[\textbf{д)}\ a^{3} - 8 = a^{3} - 2^{3} =\]
\[= (a - 2) \cdot (a^{2} + 2a + 4)\]
\[\textbf{е)}\text{\ b}^{3} + 27 = b^{3} + 3^{3} =\]
\[= (b + 3) \cdot (b^{2} - 3b + 9)\]