Divide 12 into two parts such that the sum of their squares is greater than twice their product by 4. The parts are?

Answer: 5 and 7
Explanation

Let's denote the two parts as x and 12 - x.

The sum of their squares is x² + (12 - x)².

Twice their product is 2x(12 - x).

According to the problem:

x² + (12 - x)² - 2x(12 - x) = 4

x² + 144 - 24x + x² - 24x + 2x² = 4

4x² - 48x + 140 = 0

x² - 12x + 35 = 0

(x - 7)(x - 5) = 0

x = 7 or x = 5

The two parts are 5 and 7.

Let's check:

5² + 7² = 25 + 49 = 74

2 × 5 × 7 = 70

74 - 70 = 4

This satisfies the condition.

The answer is 5 and 7.

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