Solution:
iv) Given equation: 
Since we are given two variables, we need to split the original expression into two quadratic expressions as
Factoring x first:
= 
= 
Factoring y now:
= 
= ![-1[ y(y+1) + 1(y+1)]](https://tex.z-dn.net/?f=-1%5B%20y%28y%2B1%29%20%2B%201%28y%2B1%29%5D)
= ![-1 [(y+1)(y+1)]](https://tex.z-dn.net/?f=-1%20%5B%28y%2B1%29%28y%2B1%29%5D)
= 
Therefore, the original expression becomes
6:00-30 minutes is 5:30
5:30-15 minutes is 5:15
5:15-45 minutes is 4:30
She started on 4:30 pm
Answer: 13.6% needed more time but then said no. 25.6% were contacted but said no.
To do this problem, you have to create a tree diagram with all of the possibilities.
The first branch separates with 20% not being contacted and 80% being contacted.
Then, the 80% branch can be broken into 12% saying no and 68% needing more time (multiply by 15% and 85%).
Then, the 68% branch can be broken into 54.4% going and 13.6 not going (multiply by 80% and 20%).
With the tree diagram, just pick the percents that you need.
5.30?
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