Question 1009346
If x+1 is a factor we plug -1 in for x and set the polynomial equal to zero to find k...
x^13 - 2x^7 + 3x + k = 0
(-1)^13 - 2(-1)^7 + 3(-1) + k = 0
-1 + 2 - 3 + k = 0
k = 2