61. Упростите выражение и найдите его значение.

Решение:

• \(3x + 2x, x = 0 \Rightarrow 5x = 5 \cdot 0 = 0\)
• \(7a - 2a, a = -\frac{1}{5} \Rightarrow 5a = 5 \cdot (-\frac{1}{5}) = -1\)
• \(28y - 7y, y = 3 \Rightarrow 21y = 21 \cdot 3 = 63\)
• \(15 + 6x + 2x, x = -7 \Rightarrow 15 + 8x = 15 + 8 \cdot (-7) = 15 - 56 = -41\)
• \(45 + 27a - 3a, a = 4 \Rightarrow 45 + 24a = 45 + 24 \cdot 4 = 45 + 96 = 141\)
• \(32 + 21y - 8y, y = -6 \Rightarrow 32 + 13y = 32 + 13 \cdot (-6) = 32 - 78 = -46\)
• \(11 - (2x + x), x = 2 \Rightarrow 11 - 3x = 11 - 3 \cdot 2 = 11 - 6 = 5\)
• \(4y + 5y, y = -0,1 \Rightarrow 9y = 9 \cdot (-0,1) = -0,9\)
• \(35x + 4x, x = 4 \Rightarrow 39x = 39 \cdot 4 = 156\)
• \(32a + 9a, a = -7 \Rightarrow 41a = 41 \cdot (-7) = -287\)
• \(14 + 7y + 3y, y = 5 \Rightarrow 14 + 10y = 14 + 10 \cdot 5 = 14 + 50 = 64\)
• \(27 + 12x - 9x, x = -4 \Rightarrow 27 + 3x = 27 + 3 \cdot (-4) = 27 - 12 = 15\)
• \(39 + 15a - 12, a = 2 \Rightarrow 27 + 15a = 27 + 15 \cdot 2 = 27 + 30 = 57\)
• \(7 + (5y - 3y), y = 1 \Rightarrow 7 + 2y = 7 + 2 \cdot 1 = 7 + 2 = 9\)
• \((11x - 6x) + 4, x = 2 \Rightarrow 5x + 4 = 5 \cdot 2 + 4 = 10 + 4 = 14\)

Ответ: Значения выражений найдены.