## zakeyadorsey Group Title Solve log7 (x – 8) – log7 3 = log7 21 2 years ago 2 years ago

1. Eyad Group Title

Try to show you work :) Whenever you stop i will help ..

2. zakeyadorsey Group Title

ok

3. zakeyadorsey Group Title

x-8/3=21

4. Eyad Group Title

Nope. Show your work step by step to see which part is hard ?

5. zakeyadorsey Group Title

no this is where im stuck at

6. Eyad Group Title

hmm,Actually thats wrong and that mean that the previous step which lead to this was wrong..

7. Eyad Group Title

Btw : here is hint $Logx=Logy$ x=y

8. zakeyadorsey Group Title

well all i did was put log7(x-8)over log7(3)=log7 21 then just took off the log7

9. Eyad Group Title

Its not $\Large \frac{Log_{7}(x-8)}{Log_{7}(3)}$ It is : $\Large Log_{7} \frac{(x-8)}{(3)}$

10. Eyad Group Title

So now u have $\Large \frac{x-8}{3}=21$ 63=x-8 x=71

11. zakeyadorsey Group Title

ok but were did you get 63

12. zakeyadorsey Group Title

ooh neverminod i got it thanks

13. Eyad Group Title

21*3

14. hamza_b23 Group Title

lets look over some basic properties such as log(a/b) = log a - log b and log(a*b)= log a + log b and if logx= log y then x=y just because everything is in the base of 7 we could use these properties as well so therefore from your question log7 (x – 8) – log7 3 = log7 21 let us use the first property on the left side and get log7((x-8)/3) = log 7 21and now let us use the third property to obtain (x-8)/3 = 21 and that will get us x-8 = 63 and now solve for x to obtain x = 71 :)

15. zakeyadorsey Group Title

thanks for the help everyone.I really needed it