✔ 最佳答案
x^2 - 10x + 25 = 0
Factor: Find two factors of 25 that sum to -10
Those factors are -5 and -5 since -5*-5 = 25 and -5 + -5 = -10
(x - 5)(x - 5) = 0
x = 5 (double root)
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Check solution:
x^2 - 10x + 25 = 0
5^2 - 10*(5) + 25 = 0
25 - 50 + 25 = 0
-25 + 25 = 0
0 = 0 (TRUE)