Function:)hope this helped
Answer:
6
Step-by-step explanation:
Substitute a = 2 , b = 4 into the expression

= 
= 
= 
= 6
Answer:
The mistake was on your second step where you took b to be +6, yet it has to be -6.
Answer:
Who can not solve that? Thats cake!!!!
3 is the answer.
Step-by-step explanation: