1 a/ -3,8+(-5,7) б) 4,521-8,35 6)-2,9-(-73) 3 2 (一)+1/(8 6 18+/-12 3 e):(一) 16 21) 4,6.1-25) 3 + 左 5 6 4 34 421 (5)(一/台場):(一) 6 + 13. (2x-12). (3-2x) = 0

1. а) −3,8 + (−5,7) = −3,8 − 5,7 = −9,5

Ответ: -9,5

1. б) 4,521 − 8,35 = -3,829

Ответ: -3,829

1. в) −2,9 − (−7,3) = −2,9 + 7,3 = 4,4

Ответ: 4,4

2. г) −\(\frac{5}{6}\) + \(\frac{3}{8}\) = \(\frac{-5*4 + 3*3}{24}\) = \(\frac{-20+9}{24}\) = - \(\frac{11}{24}\)

Ответ: - \(\frac{11}{24}\)

2. д) \(\frac{5}{6}\) + (-\(\frac{7}{9}\)) = \(\frac{5*3 - 7*2}{18}\) = \(\frac{15-14}{18}\) = \(\frac{1}{18}\)

Ответ: \(\frac{1}{18}\)

2. e) \(\frac{5}{16}\) : (-\(\frac{3}{8}\)) = \(\frac{5}{16}\) * (-\(\frac{8}{3}\)) = -\(\frac{5*8}{16*3}\) = -\(\frac{5}{2*3}\) = -\(\frac{5}{6}\)

Ответ: -\(\frac{5}{6}\)

2. ж) 4,6 ⋅ (−2,5) = -11,5

Ответ: -11,5

3. а) (-\(\frac{3}{7}\) + \(\frac{5}{6}\)) : (-\(\frac{34}{42}\)) = (\(\frac{-3*6 + 5*7}{42}\)) : (-\(\frac{34}{42}\)) = \(\frac{-18+35}{42}\) : (-\(\frac{34}{42}\)) = \(\frac{17}{42}\) : (-\(\frac{34}{42}\)) = \(\frac{17}{42}\) * (-\(\frac{42}{34}\)) = - \(\frac{1}{2}\) = -0,5

Ответ: -0,5

3. б) (-\(\frac{11}{12}\) + \(\frac{8}{9}\)) : (-\(\frac{5}{8}\) + \(\frac{7}{12}\)) = (\(\frac{-11*3 + 8*4}{36}\)) : (\(\frac{-5*3 + 7*2}{24}\)) = (\(\frac{-33+32}{36}\)) : (\(\frac{-15+14}{24}\)) = -\(\frac{1}{36}\) : (-\(\frac{1}{24}\)) = -\(\frac{1}{36}\) * (-24) = \(\frac{24}{36}\) = \(\frac{2}{3}\)

Ответ: \(\frac{2}{3}\)

3. (2x − 12) ⋅ (3 − x) = 0

2x - 12 = 0 или 3 - x = 0

2x = 12 или x = 3

x = 6

Ответ: x = 6, x = 3

Ответ: x = 6, x = 3