Вычислите: 42^2:28-5^2.

\[42^{2}\ :28 - 5^{2} =\]

\[= 42 \cdot 42\ :28 - 5 \cdot 5 =\]

\[= 1764\ :28 - 25 = 63 - 25 =\]

\[= 38\]