1. **State the problem:** We need to find expressions for A, B, and C in the algebraic sums given.
2. **Recall the example:**
- $2a + 3a = 5a$
- $4a + 7a = 12a$
This shows that like terms (same variable) are added by summing their coefficients.
3. **Given expressions:**
- First sum: $4k + 6n + 2k + 3n + A$
- Second sum: $B + 5k + 7n$
- Third sum: $C$
4. **Find B:**
Combine like terms in the first sum except $A$:
$$4k + 2k = 6k$$
$$6n + 3n = 9n$$
So,
$$B = 6k + 9n$$
5. **Find C:**
Add $B$ and $5k + 7n$:
$$B + 5k + 7n = (6k + 9n) + 5k + 7n = (6k + 5k) + (9n + 7n) = 11k + 16n$$
So,
$$C = 11k + 16n$$
6. **Find A:**
$A$ is the sum of the entire expression, which is $4k + 6n + 2k + 3n + 5k + 7n$.
Combine all like terms:
$$4k + 2k + 5k = 11k$$
$$6n + 3n + 7n = 16n$$
So,
$$A = 11k + 16n$$
**Final answers:**
- $A = 11k + 16n$
- $B = 6k + 9n$
- $C = 11k + 16n$
Expressions Abc Aaf39C
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