## anonymous one year ago help

1. anonymous

@Michele_Laino

2. Michele_Laino

after $$N$$ weeks, Eduardo spends $$7500+300 \cdot N$$

3. Michele_Laino

and after $$N$$ weeks he earns $$850 \cdot N$$, so Eduardo will have a profit if the subsequent condition holds: $850 \cdot N \geqslant 7500 + 300 \cdot N$ namely earnings are greater or equal than expenses

4. Michele_Laino

please you have to solve that inequality

5. anonymous

Idk how

6. Michele_Laino

If I subtract $$300N$$ from both sides I get this: $850N - 300N \geqslant 7500 + 300N - 300N$ please simplify

7. anonymous

would that be 850-300 for the first part?

8. Michele_Laino

yes!

9. anonymous

Ok! 550 right?

10. Michele_Laino

correct! and what is +350-350=...?

11. Michele_Laino

oops.. what is +300-300=...?

12. anonymous

0

13. anonymous

I think

14. Michele_Laino

ok! so we get this inequality: $550N > 7500$

15. anonymous

ok

16. Michele_Laino

I wrote $$>$$ because it is better than $$\geqslant$$

17. anonymous

ok

18. anonymous

so what would I have to do next?

19. Michele_Laino

now, we have to divide both side by 550, so we have: $\frac{{550N}}{{550}} > \frac{{7500}}{{550}}$ please simplify again

20. anonymous

How would I simplify those

21. Michele_Laino

what is 7500/550=...?

22. anonymous

13.636

23. Michele_Laino

and what is 550/550=...?

24. anonymous

1

25. Michele_Laino

ok so we get this: $$1 \cdot N > 13.6363...$$

26. Michele_Laino

since the number of week has to be a whole number we can choose N=14

27. anonymous

so it would be 14 weeks?

28. Michele_Laino

yes!

29. anonymous

Oh ok thanks

30. Michele_Laino

:)

31. anonymous

I have one more

32. anonymous

@Michele_Laino

33. Michele_Laino

If I call with P the age of Pat and with R the age of Ron, then from the text of your problem, I can write this: $\begin{gathered} 2P + 5 = R \hfill \\ P + R < 35 \hfill \\ \end{gathered}$

34. anonymous

ok

35. anonymous

I'm sorry my internet went down for a few minutes