Final answer:
To prove that 252 equals (20 + 5) squared, we use the Square of a Binomial identity, which upon expansion and simplification confirms that (20 + 5)^2 equals 625.
Step-by-step explanation:
To prove that 252 = (20 + 5)2, the correct polynomial identity to use is the Square of a Binomial. This identity states that the square of a binomial (a + b)2 is equal to a2 + 2ab + b2. By applying this identity, we can expand (20 + 5)2 as follows:
- Square the first term: 202 = 400.
- Multiply the first term by the second term and then by 2: 2 × 20 × 5 = 200.
- Square the second term: 52 = 25.
- Add these results together: 400 + 200 + 25 = 625.
Therefore, (20 + 5)2 = 625 which confirms our original statement.