Здравствуйте, ребята! Сейчас мы с вами решим задания из этой контрольной работы.
**№1 (ВПР №1). Вычислите:**
1) $$-27 + 72 : 9 = -27 + 8 = -19$$
2) $$-12 + 17 \cdot 5 = -12 + 85 = 73$$
3) $$-45 + 14 \cdot 9 = -45 + 126 = 81$$
4) $$-21 + 98 : 7 = -21 + 14 = -7$$
5) $$13 \cdot 3 - 68 = 39 - 68 = -29$$
**№2 (ВПР №2). Вычислите:**
1) $$\frac{2}{3} - \frac{5}{18} : \frac{15}{27} = \frac{2}{3} - \frac{5}{18} \cdot \frac{27}{15} = \frac{2}{3} - \frac{5 \cdot 27}{18 \cdot 15} = \frac{2}{3} - \frac{135}{270} = \frac{2}{3} - \frac{1}{2} = \frac{4}{6} - \frac{3}{6} = \frac{1}{6}$$
2) $$(-4 + 0,125) \cdot 8 = (-4 + \frac{1}{8}) \cdot 8 = (-4 + 0,125) \cdot 8 = -3,875 \cdot 8 = -31$$
3) $$2 - \frac{16}{33} : \frac{24}{55} = 2 - \frac{16}{33} \cdot \frac{55}{24} = 2 - \frac{16 \cdot 55}{33 \cdot 24} = 2 - \frac{880}{792} = 2 - \frac{10}{9} = \frac{18}{9} - \frac{10}{9} = \frac{8}{9}$$
4) $$(-7,1 + 2,7) \cdot 0,8 = -4,4 \cdot 0,8 = -3,52$$
5) $$\frac{8}{35} \cdot (\frac{5}{6} + \frac{11}{12}) = \frac{8}{35} \cdot (\frac{10}{12} + \frac{11}{12}) = \frac{8}{35} \cdot \frac{21}{12} = \frac{8 \cdot 21}{35 \cdot 12} = \frac{168}{420} = \frac{2}{5}$$
6) $$(-6,9 + 2,1) : 2,4 = -4,8 : 2,4 = -2$$
7) $$(\frac{6}{5} - \frac{3}{4}) \cdot \frac{2}{3} = (\frac{24}{20} - \frac{15}{20}) \cdot \frac{2}{3} = \frac{9}{20} \cdot \frac{2}{3} = \frac{9 \cdot 2}{20 \cdot 3} = \frac{18}{60} = \frac{3}{10}$$
8) $$1,54 + 0,5 \cdot (-1,3) = 1,54 - 0,65 = 0,89$$
9) $$(\frac{6}{5} - \frac{3}{4}) \cdot \frac{2}{3} = (\frac{24}{20} - \frac{15}{20}) \cdot \frac{2}{3} = \frac{9}{20} \cdot \frac{2}{3} = \frac{9 \cdot 2}{20 \cdot 3} = \frac{18}{60} = \frac{3}{10}$$
**№3 (ВПР №8) Решите уравнения:**
1) $$6x - 8 = 5x - 3(x - 4)$$
$$6x - 8 = 5x - 3x + 12$$
$$6x - 8 = 2x + 12$$
$$6x - 2x = 12 + 8$$
$$4x = 20$$
$$x = 5$$
2) $$3x - 2(3x - 2) = 19$$
$$3x - 6x + 4 = 19$$
$$-3x = 19 - 4$$
$$-3x = 15$$
$$x = -5$$
3) $$2(7x + 11) - 5x = 5x$$
$$14x + 22 - 5x = 5x$$
$$9x + 22 = 5x$$
$$9x - 5x = -22$$
$$4x = -22$$
$$x = -\frac{22}{4} = -\frac{11}{2} = -5,5$$
4) $$10 - 5(2x - 1) = 7$$
$$10 - 10x + 5 = 7$$
$$15 - 10x = 7$$
$$-10x = 7 - 15$$
$$-10x = -8$$
$$x = \frac{-8}{-10} = \frac{4}{5} = 0,8$$
**Ответы:**
* **№1:** 1) -19, 2) 73, 3) 81, 4) -7, 5) -29
* **№2:** 1) 1/6, 2) -31, 3) 8/9, 4) -3.52, 5) 2/5, 6) -2, 7) 3/10, 8) 0.89, 9) 3/10
* **№3:** 1) x = 5, 2) x = -5, 3) x = -5.5, 4) x = 0.8