The number of integral solutions of x+y+z=0 with x≥−5,y≥−5,z≥−5 is
134
136
138
140
Let x1=x+5,y1=y+5,z1=z+5 and find the number of non-negative integral solutions of x1+y1+z1=15.
15+3-1C3=17C3=136