Тест по математике на тему"Уравнения"

1) 5;

2) 10;

3) 4.

1) 15 + x: = 55,  x = 40;

3) 60 - y = 45,  y = 15;

5) 88 : x = 8,  x = 11;

2) х - 22 = 42,  x = 64;

4) у * 12 = 12,  y = 1;

6) у : 10 = 40,  y = 400.

1) 8x = 0;

2) 0 : y = 25;

3) 5х = 5

4) 12 : y = 0?

1)28 + (45 + х) = 100;

• 45 + x = 100 - 28;

• 45 + x = 72;

• x = 72 - 45;

• x = 27;

2) (у - 25) + 18 = 40;

• y - 25 = 40 - 18;

• y - 25 = 22;

• y = 22 + 25;

• y = 47;

3) (70 - х) - 35 = 12;

• 70 - x = 35 + 12;

• 70 - x = 47;

• x = 70 - 47;

• x = 23;

4) 60 -(y + 34) = 5;

• y + 34 = 60 - 5;

• y + 34 = 55;

• y = 55 - 34;

• y = 21;

5) 52 - (19 + х) = 17;

• 19 + x = 52 - 17;

• 19 + x = 35;

• x = 35 - 19;

• x = 16;

6) 9y - 18 = 72;

• 9y = 72 + 18;

• 9y = 90;

• y = 90 : 9;

• y = 10;

7) 20 + 5х = 100;

• 5x = 100 - 20;

• 5x = 80;

• x = 80 : 5;

• x = 16;

8) 90 - y * 12 = 78;

• y * 12 = 90 - 78;

• y * 12 = 12;

• y = 12 : 12;

• y = 1;

9) 10х - 44 = 56;

• 10x = 56 + 44;

• 10x = 100;

• x = 100 : 10;

• x = 10;

10) 84 - 7у = 28;

• 7y = 84 - 28;

• 7y = 56;

• y = 56 : 7;

• y = 8;

11) 121 : (х - 45) = 11;

• x - 45 = 121 : 11;

• x - 45 = 11;

• x = 45 + 11;

• x = 56;

12) 77 : (у + 10) = 7;

• y + 10 = 77 : 7;

• y + 10 = 11;

• y = 11 - 10;

• y = 1;

13) (х - 12) : 10 = 4;

• x - 12 = 10 * 4;

• x - 12 = 40;

• x = 40 + 12;

• x = 52;

14) 55 - y * 10 = 15;

• y * 10 = 55 - 15;

• y * 10 = 40;

• y = 40 : 10;

• y = 4;

15) х : 12 + 48 = 91;

• x : 12 = 91 - 48;

• x : 12 = 43;

• x = 43 * 12;

• x = 516;

16) 5y + 4y = 99;

• 9y = 99;

• y = 99 : 9;

• y = 11;

17) 54х - 27х = 81;

• 27x = 81;

• x = 81 : 27;

• x = 3;

18) 36y - 16y + 5y = 0;

• 25y = 0;

• y = 0 : 25;

• y = 0;

19) 14х + х - 9х + 2 = 56;

• 6x + 2 = 56;

• 6x = 56 - 2;

• 6x = 54;

• x = 54 : 6;

• x = 9;

20) 20y - 14у + 7у - 13 = 13.

• 13y - 13 = 13;

• 13y = 13 + 13;

• 13y = 26;

• y = 26 : 13;

• y = 2;

1) 65 + (х + 23) = 105;

• x + 23 = 105 - 65;

• x + 23 = 40;

• x = 40 - 23;

• x = 17;

2) (у - 34) - 10 = 32;

• y - 34 = 32 + 10;

• y - 34 = 42;

• y = 42 + 34;

• y = 76;

3) (48 - х) + 35 = 82;

• 48 - x = 82 - 35;

• 48 - x = 47;

• x = 48 - 47;

• x = 1;

4) 77 - (28 + y) = 27;

• 28 + y = 77 - 27;

• 28 - y = 50;

• y = 50 - 28;

• y = 22;

5) 90 + y * 8 = 154;

6) 9х + 50 = 86;

• 9x = 86 - 50;

• 9x = 36;

• x = 36 : 9;

• x = 4;

7) 120 : (х - 19) = 6;

• x - 19 = 120 : 6;

• x - 19 = 20;

• x = 19 + 20;

• x = 39;

8)(y + 50) : 14 = 4;

• y + 50 = 14 * 4;

• y + 50 = 56;

• y = 56 - 50;

• y = 6;

9) 48 + у : 6 = 95;

• y : 6 = 95 - 48;

• y : 6 = 47;

• y = 6 * 47;

• y = 282;

10) 8х + 7х - х = 42.

• 14x = 42;

• x = 42 : 14;

• x = 3;

а) 8;

б) 14.

а) 2y = 16;

б) x + 7 = 21.