Question 585102
-2x(5x-4x+13)

**THE 5x IS SQUARED**
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{{{-2x*((5x)^2 - 4x + 13)}}}
Did you want to multiply?  You didn't say.
{{{-2x*(25x^2 - 4x + 13) = -50x^3 + 8x^2 - 26x}}}
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Use x^2 for x squared.