Answer:
6x+2
Step-by-step explanation:
your combine like terms...
so 13x is teh same as -7x
13x-7x= 6x
3 and -1 are the same as well
3-1=2
so teh answer would be
6x+2
Answer:
3=111
Step-by-step explanation:
1+3+5+7+...+999 =
= 1+2+3+4+...+500
+1+2+3+...+499
= 2·(1+2+3+...+499) + 500
= 2·(499·500)/2 + 500
= 499·500 + 500
= 500·(499 + 1)
= 500·500
= 250.000
