Question

СРОЧНО УМОЛЯЮ!!! 1. Решите уравнение: а) 5х – 6 = 8; б) 6х – 2х + 4 = 8; в) 9 – 3/5 • х = 16. 2. Решите с помощью уравнения задачу. Задумали число, прибавили к нему 15 и результат умножили на 3. Получилось 144. Какое число задумали? 3. Решите с помощью уравнения задачу. В одном мотке лески на 9 м больше, чем в другом, а всего в двух мотках 27 м лески. Сколько лески в каждом мотке? 4. Найдите значение выражения 5х – 17 при х = 3 целых 1/2. 5. Упростите выражение 7х – 6 – (9х – 7). 6. Зависит ли от значения х значение выражения 6(3х – 3) – 2(5х + 1) – (8х + 3)?

Answer 1

Ответ:

6 задание не знаю. если есть вопросы - пишите

Answer 2

1. Решение уравнений:

а) 5х – 6 = 8

To solve this equation, we want to isolate the variable x on one side of the equation. First, let's add 6 to both sides to get:

5х – 6 + 6 = 8 + 6 5х = 14

Next, divide both sides by 5 to solve for x:

(5х)/5 = 14/5 х = 14/5

Therefore, the solution is x = 14/5.

б) 6х – 2х + 4 = 8

To solve this equation, we want to combine like terms and isolate the variable x. First, combine the x terms:

6х – 2х = 4 4х = 4

Next, divide both sides by 4 to solve for x:

(4х)/4 = 4/4 х = 1

Therefore, the solution is x = 1.

в) 9 – (3/5) • х = 16

To solve this equation, we want to isolate the variable x. First, distribute the (3/5) to the х term:

9 - (3/5) • х = 16 9 - (3/5)х = 16

Next, subtract 9 from both sides:

9 - 9 - (3/5)х = 16 - 9 -(3/5)х = 7

To get rid of the negative sign, multiply both sides by -1:

-1 * (-(3/5)х) = -1 * 7 (3/5)х = -7

Finally, divide both sides by (3/5) to solve for x:

((3/5)х) / (3/5) = -7 / (3/5) х = -7 * (5/3)

Simplifying the expression gives:

х = -35/3

Therefore, the solution is x = -35/3.

2. Решение задач с помощью уравнений:

2.1 Задумали число, прибавили к нему 15 и результат умножили на 3. Получилось 144. Какое число задумали?

Let's assume the unknown number is represented by x. According to the problem, we can write the equation:

3(x + 15) = 144

To solve for x, we need to isolate it. First, distribute the 3 to the terms inside the parentheses:

3x + 45 = 144

Next, subtract 45 from both sides:

3x + 45 - 45 = 144 - 45 3x = 99

Finally, divide both sides by 3:

(3x)/3 = 99/3 x = 33

Therefore, the number that was initially thought of is 33.

2.2 В одном мотке лески на 9 м больше, чем в другом, а всего в двух мотках 27 м лески. Сколько лески в каждом мотке?

Let's assume the amount of string in one spool is represented by x. According to the problem, we can write the equation:

x + (x + 9) = 27

To solve for x, we need to simplify and combine like terms:

2x + 9 = 27

Next, subtract 9 from both sides:

2x + 9 - 9 = 27 - 9 2x = 18

Finally, divide both sides by 2:

(2x)/2 = 18/2 x = 9

Therefore, there are 9 meters of string in one spool, and 9 + 9 = 18 meters of string in the other.

3. Вычисление значений выражений:

4. Найдите значение выражения 5х – 17 при х = 3 целых 1/2.

To find the value of the expression 5х - 17 when x is equal to 3 and a half, we substitute x = 3 1/2 into the expression:

5(3 1/2) - 17

First, convert the mixed number 3 1/2 to an improper fraction:

3 1/2 = 7/2

Now, substitute the value of x:

5(7/2) - 17

Next, perform the multiplication:

35/2 - 17

To subtract these fractions, we need a common denominator. The least common multiple of 2 and 1 is 2:

35/2 - 17 * 2/2

35/2 - 34/2

Now, subtract the fractions:

(35 - 34)/2 = 1/2

Therefore, the value of the expression 5х - 17 when x = 3 1/2 is 1/2.

5. Упростите выражение 7х - 6 - (9х - 7).

To simplify the expression 7х - 6 - (9х - 7), we need to distribute the negative sign to the terms inside the parentheses:

7х - 6 - 9х + 7

Next, combine like terms:

(7х - 9х) - 6 + 7

-2х + 1

Therefore, the simplified expression is -2х + 1.

6. Зависит ли от значения х значение выражения 6(3х - 3) - 2(5х + 1) - (8х + 3)?

To determine if the value of the expression 6(3х - 3) - 2(5х + 1) - (8х + 3) depends on the value of x, we can simplify the expression:

6(3х - 3) - 2(5х + 1) - (8х + 3)

First, distribute the coefficients:

18х - 18 - 10х - 2 - 8х - 3

Next, combine like terms:

(18х - 10х - 8х) - (18 + 2 + 3)

(18 - 10 - 8)х - (18 + 2 + 3)

Therefore, the expression simplifies to (18 - 10 - 8)х - (18 + 2 + 3) = 0. The value of the expression is always 0, regardless of the value of x.