Step-by-step explanation: To evaluate functions substitute the given number or expression function's variable.
Answer:
+
Step-by-step explanation:
++ = +
+- = -
-+ = -
-- = +
Example:
-1 x -1 = 1
1 x -1 = -1
Answer:
13a
Step-by-step explanation:
9a + 3a + a = 13a
Answer:Blue
Step-by-step explanation: