\[\boxed{\mathbf{2.}\mathbf{151.ОК\ ГДЗ - домашка\ на\ }5}\]
Пояснение.
Решение.
\[\textbf{а)}\ x - 47 - 38 =\]
\[= x - (47 + 38) = x - 85\]
\[x = 625:\]
\[625 - 85 = 540.\]
\[\textbf{б)}\ 168 + y - 68 =\]
\[= y + (168 - 68) = y + 100\]
\[y = 77:\]
\[77 + 100 = 177.\]
\[\textbf{в)}\ 137 + a + 263 =\]
\[= a + (137 + 263) = a + 400\]
\[a = 194:\]
\[194 + 400 = 594.\]
\[a = 381:\]
\[381 + 400 = 781.\]
\[\textbf{г)}\ z - 135 + 215 =\]
\[= z + (215 - 135) = z + 80\]
\[z = 329:\]
\[329 + 80 = 409.\]
\[z = 918:\]
\[918 + 80 = 998.\]