Question

A + B + C=? A+B=9B-C=3C+1=4А) 3В) 9С) 12D) 13E) 15​

Answer 1

1) Найдем С.

С+1=4

С=4-1

С=3

2) Найдем В.

В-С=3

В-3=3

В=6

3) Найдем А.

A+B=9

А+6=9

А=3

4) Найдем сумму.

А+В+С=3+6+3=12

Ответ: 12

Answer 2

To find the values of A, B, and C, you can use the given equations:

1. A + B = 9
2. B - C = 3
3. C + 1 = 4

Let's solve this step by step:

From equation 3, we can see that C = 4 - 1 = 3.

Now, we can substitute the value of C into equation 2:

B - 3 = 3

Add 3 to both sides:

B = 3 + 3 B = 6

Now that we have the values of B and C, we can find A using equation 1:

A + 6 = 9

Subtract 6 from both sides:

A = 9 - 6 A = 3

So, the values of A, B, and C are:

A = 3 B = 6 C = 3

Now, you can calculate A + B + C:

3 + 6 + 3 = 12

So, A + B + C = 12.

The correct answer is option (C) 12.