Question 196101
I need your help in add\subtract Polynomials as in this problem 
{{{(5x^3+x-4)+(6x^2-3x-5)}}}
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Collect like terms.  There's only one x^3 term and one x^2 term.
There's x in the 1st and -3x in the 2nd term.  That totals -2x.
Then add -4 and -5, = -9.
{{{5x^3 + 6x^2 - 2x - 9}}}