Пошаговое решение:
- Блок 5, Задание а:
\( 784 - (980 - 2y) = 16 \)
\( 784 - 980 + 2y = 16 \)
\( -196 + 2y = 16 \)
\( 2y = 16 + 196 \)
\( 2y = 212 \)
\( y = 212 / 2 \)
\( y = 106 \) - Блок 5, Задание б:
\( 256 : (160 - 2y) = 8 \)
\( 160 - 2y = 256 / 8 \)
\( 160 - 2y = 32 \)
\( -2y = 32 - 160 \)
\( -2y = -128 \)
\( y = -128 / -2 \)
\( y = 64 \) - Блок 5, Задание в:
\( 6 × (25y - 18) = 642 \)
\( 25y - 18 = 642 / 6 \)
\( 25y - 18 = 107 \)
\( 25y = 107 + 18 \)
\( 25y = 125 \)
\( y = 125 / 25 \)
\( y = 5 \) - Блок 5, Задание г:
\( 10 × (25y + 130) - 534 = 1766 \)
\( 10 × (25y + 130) = 1766 + 534 \)
\( 10 × (25y + 130) = 2300 \)
\( 25y + 130 = 2300 / 10 \)
\( 25y + 130 = 230 \)
\( 25y = 230 - 130 \)
\( 25y = 100 \)
\( y = 100 / 25 \)
\( y = 4 \) - Блок 5, Задание д:
\( 1452 - (6y + 8) : 8 = 1459 - 7 \)
\( 1452 - (6y + 8) : 8 = 1452 \)
\( - (6y + 8) : 8 = 1452 - 1452 \)
\( - (6y + 8) : 8 = 0 \)
\( (6y + 8) : 8 = 0 \)
\( 6y + 8 = 0 × 8 \)
\( 6y + 8 = 0 \)
\( 6y = -8 \)
\( y = -8 / 6 \)
\( y = -4/3 \) - Блок 5, Задание е:
\( 1452 - (6z - 8) : 5 = 698 + 746 \)
\( 1452 - (6z - 8) : 5 = 1444 \)
\( - (6z - 8) : 5 = 1444 - 1452 \)
\( - (6z - 8) : 5 = -8 \)
\( (6z - 8) : 5 = 8 \)
\( 6z - 8 = 8 × 5 \)
\( 6z - 8 = 40 \)
\( 6z = 40 + 8 \)
\( 6z = 48 \)
\( z = 48 / 6 \)
\( z = 8 \)
Ответ:
а) y = 106
б) y = 64
в) y = 5
г) y = 4
д) y = -4/3
е) z = 8