Question

Если к задуманному числу прибавить 9, полученную сумму умножить на 4 и из произведения вычесть 72, то получится задуманное число. Найди это число. Решите пожалуйста с объяснениями, спасибо))

Answer 1

Пусть х -- задуманное число. Тогда:
4*(x + 9) - 72 = x
4x + 36 - 72 = x
Перенесем слагаемые с переменной в одну сторону, числа -- в другую.
4x - x = 72 - 36
3x = 36
x = 36/3 = 12
Ответ: 12.

Answer 2

Problem Analysis

The problem states that if we add 9 to a certain number, multiply the sum by 4, and then subtract 72 from the product, we will obtain the original number. We need to find this number.

Solution

Let's assume the unknown number is represented by the variable x.

According to the problem, the steps to find the unknown number are as follows: 1. Add 9 to the unknown number: x + 9 2. Multiply the sum by 4: 4(x + 9) 3. Subtract 72 from the product: 4(x + 9) - 72

According to the problem statement, the result of this calculation should be equal to the original number x. Therefore, we can set up the equation:

4(x + 9) - 72 = x

Now, let's solve this equation to find the value of x.

Solving the Equation

To solve the equation, we will simplify and isolate the variable x.

Expanding the equation: 4x + 36 - 72 = x

Combining like terms: 4x - 36 = x

Subtracting x from both sides: 3x - 36 = 0

Adding 36 to both sides: 3x = 36

Dividing both sides by 3: x = 12

Therefore, the unknown number is 12.

Conclusion

The unknown number is 12. When we add 9 to 12, multiply the sum by 4, and subtract 72 from the product, we obtain the original number 12.

Please let me know if you need any further assistance!