The Official Homework Help Thread!

[KimHeeSung]

I will be needing this, thank you 

[KimHeeSung]

I need help  :cry:  Im in geometry, and we are starting with some basic algebra and all that good stuff, but I kinda forgot some steps and I have a quiz tomorrow. I went over my notes but i have no idea what i did so yeah..

 

both of them are fractions btw..so 3x over 5 equals 4 over 3 and we are solving for x.

 

3x/5 = 4/3

[KimHeeSung]

cross multiply the denominators,

3x*3 = 4* 5

simplify,

9x = 20

then divide both sides by 9

x = 20/9

 

hope that helps! If youre confused feel free to ask~

 

ahh that makes more sense..thank you!~

 

[spoiler]i love your sig btw [/spoiler]

[KimHeeSung]

thanks! but jimin in your sig tho  :ahmagah:

 

haha  :chu:

 

 

i got the same answer too but did it differently

get rid of the 5 from 3x by multiplying it to 4/3

3x= 4/3 * 5 = 20/3

then divide the 3 from the 3x to get the x by itself

x= 20/9

 

Thank you guys so much!~  :rlytearpls:

 

I can help with biology or any health science related stuff and some math depending on what it is~

[KimHeeSung]

One more question..how would you solve this? 

 

[KimHeeSung]

Since you have to solve for c, you can start by rearranging the equation to make 'c' alone on one side (the subject of the formula)

so divide both sides by mT (to leave c alone on the left side)

q/mT = c

then you can substitute the values for the variables

-302/(5.37 * -35) = c

then solve it with your calculator

 

Ohhh..i kept subtracting C from both sides..no wonder. 

 

Thank you so much again~ 

[KimHeeSung]

haha no problem~

what do you have as the answer btw?

1968.34264?

[KimHeeSung]

Can you help me with these..

 

-29.5 = 9 + 4.5(d-8)

 

and

 

5 - 2.5(1.9.5x) = 18.5

[KimHeeSung]

Hope someone here is good at chem, because I've been staring at my prelab for 10 min :rlytearpls:

I got the balanced equation already but I'm not sure what we do to find the needed grams? Am i suppose to use the gram to mole to gram conversion and use the grams from the periodic table and the moles from the balanced equation?? my friends don't know shit so pls help lmao

 

[spoiler]

 

[/spoiler]

[KimHeeSung]

Yes, this is stoichiometry. The balanced chemical reaction tells you that every one molecule of CaCl2 reacts with one molecule of Na2CO3. That means on a larger scale, each mole of CaCl2 reacts with one mole of Na2CO3. So you need the moles of Na2CO3 to be the same as the moles of CaCl2 used. Thus, given grams of CaCl2, you can find out how many mol of CaCl2 were used, state that that is equal to the mol of Na2CO3 is needed and thus calculate how many grams of Na2CO3 are needed.

 

I'm kinda confused on that part, everything else made sense. We have to use the ladder method for all conversions so does that mean I start off by adding all the masses for CaCl2 and use that to start the conversion because we aren't given any amount for the grams of CaCl2 used?