Уравнения и формулы

Решите уравнение: 2x + 5 = 17

• x = 6

• x = 15

• x = 10

• x = 8

Answer explanation

To solve the equation 2x + 5 = 17, first subtract 5 from both sides to get 2x = 12. Then divide by 2 to find x = 6. Therefore, the correct answer is x = 6.

Найдите значение переменной: y = 3x^2 + 2x - 5, при x = 2

• 11

• 7

• 15

• -1

Answer explanation

Substitute x = 2 into y = 3x^2 + 2x - 5 to get y = 3(2)^2 + 2(2) - 5 = 12 + 4 - 5 = 11. Therefore, the value of y when x = 2 is 11.

Решите уравнение: 4y - 7 = 5

• y = 4

• y = 2

• y = 6

• y = 3

Answer explanation

To solve the equation, add 7 to both sides to isolate 4y. This gives 4y = 12. Then, divide by 4 to find y = 3. Therefore, the correct answer is y = 3.

Выразите x из уравнения: 3(x + 2) = 15

• x = 6

• x = 3

• x = 5

• x = 4

Answer explanation

To solve the equation, first distribute the 3: 3x + 6 = 15. Then, subtract 6 from both sides: 3x = 9. Finally, divide by 3 to find x = 3.

Найдите значение выражения: 2a^2 - 3a + 1, при a = 4

• 25

• 16

• 21

• 19

Answer explanation

Substitute a = 4 into the expression: 2(4)^2 - 3(4) + 1 = 2(16) - 12 + 1 = 32 - 12 + 1 = 20 + 1 = 21. Therefore, the value of the expression is 21.

Решите уравнение: 6z + 9 = 3z - 4

• z = 0

• z = 5

• z = -13

• z = -7

Answer explanation

Subtracting 3z from both sides gives 3z + 9 = -4. Then subtracting 9 from both sides gives 3z = -13. Finally, dividing by 3 gives z = -13.

Найдите значение переменной: p = 2q^2 - 5q + 3, при q = 3

• 7

• 8

• 10

• 6

Answer explanation

Substitute q = 3 into p = 2q^2 - 5q + 3 to get p = 2(3)^2 - 5(3) + 3 = 18 - 15 + 3 = 6. Therefore, the value of p is 6.

Решите уравнение: 8m - 3 = 5m + 12

• m = 3

• m = 7

• m = 10

• m = 5

Answer explanation

To solve the equation, first, combine like terms: 8m - 5m = 12 + 3. This simplifies to 3m = 15. Then, divide by 3 to find m = 5. Therefore, the correct answer is m = 5.

Выразите y из уравнения: 2(y - 4) = 10

• y = 7

• y = 5

• y = 9

• y = 12

Answer explanation

To solve for y, first distribute the 2: 2y - 8 = 10. Then, add 8 to both sides: 2y = 18. Finally, divide by 2 to find y = 9. Therefore, the correct answer is y = 9.

Найдите значение выражения: 5b^2 + 2b - 7, при b = -2

• 9

• 3

• 13

• -9

Answer explanation

Substitute b = -2 into the expression: 5(-2)^2 + 2(-2) - 7 = 5(4) - 4 - 7 = 20 - 4 - 7 = 16 - 7 = 9. Therefore, the value of the expression is 9.