X^2 + 20x + 100 = 4 - 4x + x^2
20x + 4x + 100 - 4 = 0
24x + 96 = 0
24x = -96
x = -4
A²+b²=29²
a+b=41
a=41-b
(41-b)²+b²=841
(41-b)(41-b)+b²=841
1681-41b-41b+b²+b²=841
2b²-82b+840=0
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0,01ab × 100a = a²b
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