Additive indentity

n = 1
a variable is always a number itself remember 7+n
5+2 = 7
Answer:
B) 40 degrees
Step-by-step explanation:
90 + 50 = 140
Each triangle have 180 °
180 - 140 = 40
They give you the same answer it just that one has parenthesis and the other one doesn't.
0,0
1,2
2,4
3,6
4,8
There u go hope u get it done