## jaylelile one year ago I'm having a hard time remembering how to go about this problem. help? Problem below

1. jaylelile

$\frac{ 4}{ 8 }^{2}b+\frac{ 40 }{ 32 }^{3}b$

2. jaylelile

@Nnesha ?

3. Nnesha

well the variables are the same so they are like terms combine them

4. Nnesha

here is an example when the variables and the exponents are the same we can add/subtract their coefficients $\rm 2x^2+5x^2 = (2+5)x^2=7x^2$

5. jaylelile

$\frac{ 44}{ 40 }^{3}b ?????$

6. Nnesha

hmm we didn't add them correctly :=) $\rm \frac{ 4}{ 8 }^{2}b+\frac{ 40 }{ 32 }^{3}b=(\frac{4^2}{8}+\frac{40^3}{32})b$

7. jaylelile

that seems too simple though.. lol

8. Nnesha

$\rm \frac{ 4}{ 8 }^{2}b+\frac{ 40 }{ 32 }^{3}b=(\frac{4^2}{8}+\frac{40^3}{32})b$ $\rm (\color{ReD}{\frac{4^2}{8}+\frac{40^3}{32}})b$ solve paretheses what's the common denominator ??

9. jaylelile

do we add the exponents?

10. jaylelile

I'm so confused

11. Nnesha

no when we multiply same bases then we should add their exponents when we combine like terms base stay the same we just have to add/subtract their coefficients

12. jaylelile

I'm still getting $\frac{ 44 }{ 40 }^{3}b$ ..........

13. Nnesha

alright show some work i mean what was your step how did you get 40 at the denominaotr ?

14. Nnesha

i see what you did there common mistake

15. jaylelile

I just added 8 and 32... is that wrong?

16. Nnesha

$\frac{ 3 }{ 2} + \frac{4}{6}$ |dw:1444530347581:dw|wrong that's not how we should add

17. jaylelile

then how do we add? I'm lost

18. Nnesha

find common denominator then multiply the numerator of first fraction by the denominator of 2nd fraction multiply the numerator of 2nd fraction by the denominator of first fraction here is an example $\huge\rm \frac{ a } {\color{Red}{ b} }+\frac{ c }{\color{blue}{ d} } =\frac{ a\color{blue}{d}+c\color{Red}{b} }{ bd}$

19. Nnesha

to make it easy write factors of 8 and 32 8 = 1 ,2 , 4 , 8 32=1 ,2 ,4 ,8 ,16 ,32 what is the common number ??

20. jaylelile

1,2, 4 and 8

21. Nnesha

brb i need to refresh the page =.=

22. Nnesha

alright sorry i made a mistake there

23. Nnesha

when denominators aren't the same we should multiply them so multiply 8 times 32 that would be the common denominator

24. Nnesha

we don't need factors sorry about that

25. Nnesha

here is an example $\huge\rm \frac{ a } {\color{Red}{ b} }+\frac{ c }{\color{blue}{ d} } =\frac{ a\color{blue}{d}+c\color{Red}{b} }{ bd}$ use this example $\frac{ 4^2 } {\color{Red}{ 8} }+\frac{ 40^3}{\color{blue}{ 32} }$

26. jaylelile

so $\frac{ 44 }{ 256 }^{3}b$ ?????

27. Nnesha

hmm no use the example you can't just add their numerator if the denominators are the same THEN you can just add the numerators $\frac{3}{\color{Red}{4}}+\frac{5}{\color{blue}{4}} = \frac{3+5}{4}$ in this example both denominators are the same so u can add their exponents

28. Nnesha

but when the denominators arn't the same multiply the numerator of first fraction by the denominator of 2nd fraction multiply the numerator of 2nd fraction by the denominator of first fraction here is an example $\huge\rm \frac{ a } {\color{Red}{ b} }+\frac{ c }{\color{blue}{ d} } =\frac{ a\color{blue}{d}+c\color{Red}{b} }{ bd}$ same like cross multiplications |dw:1444531460579:dw|

29. Nnesha

make sense hmm ?

30. Nnesha

btw you can reduce the fraction before adding them but well let's stik with it

31. anonymous

$\frac{ 4^2 }{ 8 }+\frac{ 40^3 }{ 32 }=\frac{ 4^3+40^3 }{ 32 }=\frac{ 4^3\left( 1^3+10^3 \right) }{ 32 }$ $=\frac{ 64\left( 1+1000 \right) }{ 32 }=2\left( 1+1000 \right)=?$

32. Nnesha

gtg in few mints so i'll just post this here just like the example i gave u $\huge\rm \frac{4^2} {\color{Red}{ 8} }+\frac{ 40^3}{\color{blue}{ 32} } =\frac{ 4^2\color{blue}{(32)}+40^3\color{Red}{(8)} }{ 256}$ now you can simplify it