Answer:
a
Step-by-step explanation:
<u>ANSWER</u>
(C) y
<u>EXPLANATION</u>
We have two equations:
The first one is

The second equation is

Let us make z the subject of this second equation:

We now add equation (1) and (3) to get:

We simplify to get:


Divide throu by 2.



The correct answer is C
Answer:
70 days
Step-by-step explanation:
that is the procedure above
C is when both are negative
it depends on how many people are in the competition