a) 10b - 7b = 3b
b) 4 + 13k - k - 5 = 12k - 1
c) -1.2c - 8d + c - 2.3d = -0.2c - 10.3d
d) \(\frac{1}{3}f + \frac{3}{19}q + f - 2\frac{5}{38}q = \frac{4}{3}f - \frac{1}{4}q\)
a) x + (c + a) = x + c + a
b) a - (5 - 3d) = a - 5 + 3d
c) 17 - (17s + 1.7) + 17s - 0.17 = 17 - 17s - 1.7 + 17s - 0.17 = 15.13
d) - (d + \(\frac{5}{17}\) - 6t) - (2d - 1 + t) = -d - \(\frac{5}{17}\) + 6t - 2d + 1 - t = -3d + 5t + \(\frac{12}{17}\)
a) 4c - 2(-1.2 + 3.2c) при c = -2.4
4c - 2(-1.2 + 3.2c) = 4c + 2.4 - 6.4c = -2.4c + 2.4
Подставим c = -2.4: -2.4 \(\cdot\) (-2.4) + 2.4 = 5.76 + 2.4 = 8.16
b) \(\frac{1}{3}\)(x - \(\frac{3}{5}\)) - 3(x + \(\frac{1}{5}\)) при x = \(\frac{1}{2}\)
\(\frac{1}{3}\)(x - \(\frac{3}{5}\)) - 3(x + \(\frac{1}{5}\)) = \(\frac{1}{3}\)x - \(\frac{1}{5}\) - 3x - \(\frac{3}{5}\) = -\(\frac{8}{3}\)x - \(\frac{4}{5}\)
Подставим x = \(\frac{1}{2}\): -\(\frac{8}{3}\) \(\cdot\) \(\frac{1}{2}\) - \(\frac{4}{5}\) = -\(\frac{4}{3}\) - \(\frac{4}{5}\) = -\(\frac{20}{15}\) - \(\frac{12}{15}\) = -\(\frac{32}{15}\)
Ответ: 1) a) 3b; b) 12k - 1; c) -0.2c - 10.3d; d) \(\frac{4}{3}\)f - \(\frac{1}{4}\)q; 2) a) x + c + a; b) a - 5 + 3d; c) 15.13; d) -3d + 5t + \(\frac{12}{17}\); 3) a) 8.16; b) -\(\frac{32}{15}\)
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