372. Решите уравнение:
a) $$x + 37 = 85$$
$$x = 85 - 37$$
$$x = 48$$
б) $$156 + y = 218$$
$$y = 218 - 156$$
$$y = 62$$
в) $$85 - z = 36$$
$$z = 85 - 36$$
$$z = 49$$
г) $$m - 94 = 18$$
$$m = 18 + 94$$
$$m = 112$$
д) $$2041 - n = 786$$
$$n = 2041 - 786$$
$$n = 1255$$
e) $$p - 7698 = 2302$$
$$p = 2302 + 7698$$
$$p = 10000$$
376. Решите уравнение и выполните проверку:
a) $$(x + 15) - 8 = 17$$
$$x + 15 = 17 + 8$$
$$x + 15 = 25$$
$$x = 25 - 15$$
$$x = 10$$
Проверка:
$$(10 + 15) - 8 = 17$$
$$25 - 8 = 17$$
$$17 = 17$$
б) $$(24 + x) - 21 = 10$$
$$24 + x = 10 + 21$$
$$24 + x = 31$$
$$x = 31 - 24$$
$$x = 7$$
Проверка:
$$(24 + 7) - 21 = 10$$
$$31 - 21 = 10$$
$$10 = 10$$
в) $$(45 - y) + 18 = 58$$
$$45 - y = 58 - 18$$
$$45 - y = 40$$
$$y = 45 - 40$$
$$y = 5$$
Проверка:
$$(45 - 5) + 18 = 58$$
$$40 + 18 = 58$$
$$58 = 58$$
г) $$(y - 35) + 12 = 32$$
$$y - 35 = 32 - 12$$
$$y - 35 = 20$$
$$y = 20 + 35$$
$$y = 55$$
Проверка:
$$(55 - 35) + 12 = 32$$
$$20 + 12 = 32$$
$$32 = 32$$
д) $$56 - (x + 12) = 24$$
$$x + 12 = 56 - 24$$
$$x + 12 = 32$$
$$x = 32 - 12$$
$$x = 20$$
Проверка:
$$56 - (20 + 12) = 24$$
$$56 - 32 = 24$$
$$24 = 24$$
e) $$55 - (x - 15) = 30$$
$$x - 15 = 55 - 30$$
$$x - 15 = 25$$
$$x = 25 + 15$$
$$x = 40$$
Проверка:
$$55 - (40 - 15) = 30$$
$$55 - 25 = 30$$
$$30 = 30$$
487. Решите уравнение:
a) $$(x - 12) \cdot 8 = 56$$
$$x - 12 = 56 \div 8$$
$$x - 12 = 7$$
$$x = 7 + 12$$
$$x = 19$$
б) $$24 \cdot (z + 9) = 288$$
$$z + 9 = 288 \div 24$$
$$z + 9 = 12$$
$$z = 12 - 9$$
$$z = 3$$
в) $$(y + 25) \div 8 = 16$$
$$y + 25 = 16 \cdot 8$$
$$y + 25 = 128$$
$$y = 128 - 25$$
$$y = 103$$
г) $$124 \div (y - 5) = 31$$
$$y - 5 = 124 \div 31$$
$$y - 5 = 4$$
$$y = 4 + 5$$
$$y = 9$$
д) $$38x + 15 = 91$$
$$38x = 91 - 15$$
$$38x = 76$$
$$x = 76 \div 38$$
$$x = 2$$
e) $$44 \div z + 9 = 20$$
$$44 \div z = 20 - 9$$
$$44 \div z = 11$$
$$z = 44 \div 11$$
$$z = 4$$