Answer:
2(4x -5)(4x +5)
Explanation:
After you remove the common factor of 2, you recognize the expression as the difference of squares. That gets factored according to its special form:
a² -b² = (a -b)(a +b)
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32x^2 -50 = 2(16x^2 -25) = 2((4x)^2 -5^2)
= 2(4x -5)(4x +5)