Math help (Elementary algebra)

[Ikith]

I've asked three people for help on how to solve this one and no one has been able to.

5/2 - x/3 = 3x

Solve for x

[Overburn]

15/20?

5/2 - x/3 = 3x

6(5/2) - 6(x/3) = 3x*6

3*5 -2x = 18x

15 -2x +2x = 18x +2x

15/x=20x/x

x= 15/20

x= 3/4

[Zilong]

10/3X = 5/2

X = 5/2 * 3/10

X = 15/20

[Kaylia]

I've asked three people for help on how to solve this one and no one has been able to.

5/2 - x/3 = 3x

Solve for x

5/2 = 3x + x/3
5/2 = 9x/3 + x/3
5/2 = 10x/3
15 = 20x
15/20= x
3/4 = x



How the fuck can you not be able to do this in your head.

[SDSD]

5/2 = 3x + x/3
5/2 = 9x/3 + x/3
5/2 = 10x/3
15 = 20x
15/20= x
3/4 = x



How the fuck can you not be able to do this in your head.

I do SAT tutoring, and you'd be surprised how many 11th and 12th graders can't do a problem like that in their head.

[Cream Soda]

5/2 - x/3 = 3x

5/2 -x/3 + x/3 = 3x + x/3

5/2 = 3x + x/3

Factor out the x

5/2 = x(3 + 1/3)

Divide to get x alone, remember to multiply denominators

5/(2 * (3 + (1/3))) = x

.75 = x

3/4 = x

[Cream Soda]

5/2 = 3x + x/3
5/2 = 9x/3 + x/3
5/2 = 10x/3
15 = 20x
15/20= x
3/4 = x



How the fuck can you not be able to do this in your head.

lol this confused the shit out of me for a sec. been so long since I've added fractions and I've always been a fan of factoring, ect.

[Mojo]

The least confusing way, imo.

[ 5/2 - x/3 = 3x  ] * 6
[ 15  - 2x  = 18x ] + 2x
[ 15        = 20x ] / 20
[ 15/20     =  x  ]

[Kaylia]

I do SAT tutoring, and you'd be surprised how many 11th and 12th graders can't do a problem like that in their head.

I hope they can do it on paper then >_>

lol this confused the shit out of me for a sec. been so long since I've added fractions and I've always been a fan of factoring, ect.

Not a huge difference between your
5/2 = x(3 + 1/3)
and my
5/2 = 9x/3 + x/3

The only difference is that you postponed the addition to the (3 + (1/3)) part, which imo is just a good way to waste ink. Its not really an issue here, but when you have huge equations, dragging something like this increase the chance of fucking up.

Add apples with apples and orange with orange as soon as you can. Nothing is gained if you keep them separated.

Factoring is useful for higher degree equation thought, since it allow you to easily solve the equation.

[Cream Soda]

Yea, was looking at it and was like oh wait, I didn't need to add that. Just a habit from calc i guess since the teacher always said show as much work as possible so I can give partial credit accordingly.

[Heavencloud]

lol this confused the shit out of me for a sec. been so long since I've added fractions and I've always been a fan of factoring, ect.

holy shit me too lol factoring ftw

[zoobernut]

15/20?

5/2 - x/3 = 3x

6(5/2) - 6(x/3) = 3x*6

3*5 -2x = 18x

15 -2x +2x = 18x +2

15/x=20x/x

x= 15/20

x= 3/4

Even though somehow you ended up with the correct answer I just wanted to point out you made a mistake in the middle. If you add something to one side you need to add exactly the same thing to the other to maintain the equality.

In the bold part on the right hand side of the equation it should be + 2x instead of + 2

The only reason I say this is because in many math classes I took your work in between was more important than the final answer and you would lose points for that.

[kuronosan]

I've asked three people for help on how to solve this one and no one has been able to.

5/2 - x/3 = 3x

Solve for x

5/2 - x/3 = 3x
5/2 = 3x + x/3
5/2 = 9x/3 + x/3
5/2 = 10x/3
15/2 = 10x
15/20 = x

Who did you ask?

[Woozie]

I've asked three people for help on how to solve this one and no one has been able to.

Yeah, you're definitely asking the wrong people then. Or your teacher must really suck. I'm betting it's the latter. Any chance you can drop that class and get a new teacher?

[LogainDiabolos]

Yeah, you're definitely asking the wrong people then. Or your teacher must really suck. I'm betting it's the latter. Any chance you can drop that class and get a new teacher?

I highly doubt its the teacher. Considering we don't know what level the OP is at making assumptions of his teachers/professors would be the wrong way to go. Maybe the OP is just really bad at math? Or maybe he/she is in elementary school?

Either way, don't blame the underpaid, overworked babysitters of the public education system. Blame the morons that won't pay attention in the babysitter's classes.

[Woozie]

I actually have experience teaching math in public schools (for free. I was still in high school myself...it's a really long story), as well as a lot of experience tutoring. Tehcnically I was supposed to just be an assistant but for a few different reasons, my teachers had to make me the primary teacher. She just graded the papers. From my own personal experiences, much of the problems students face do in fact come from the teachers. Yes, I was probably wrong for automatically jumping to that conclusion. Not all teachers, are bad. Some of them really are trying and the students are just acting up. I've had that happen in classes I taught.

But much more often than not, the teachers are a much bigger problem than they care to admit to. Same thing goes in college. When I was 16/17/18 years old I had much better results than teachers who were in the field for 10~15 years or longer. You can't tell me it's always just the students.

Edit: And the whole "underpaid overworked babysitters" attitude is the reason so many teachers suck at what they do. They're actually right, they are underpaid and overworked babysitters, but the teachers who come to work with the "Well I love what I do so I'll tolerate this if I can" attitude are always more effective than the "This job sucks I should have went to grad school for Biology" teachers. Though we shouldn't be having this discussion anyways because teachers should get paid more and get to work under better conditions rather than get tossed in a room with with 50 students but 30 seats and have to cater to students who don't want to learn instead of educating those who really do. I could write a whole book about my issues with our system, but I'll hold back on that for now.

[Ikith]

Its actually not the teacher. I was sick yesterday and didn't want to get points knocked off of my homework so I decided to do it anyway. Come to find out she made a mistake and didn't even cover doing fractions like that in class and gave extra credit to all of us who did them anyway (she also said there would be no fractions in the problems she assigned). So yeah it is my fault but at that point it was out of my control (waking up and throwing up is not fun).

Thank you all for the help I aced my assignment and that was the only one I got stuck on really. I had been doing it right but somewhere in my process I fucked up so I thought I was stuck.

[Woozie]

Yes, I was probably wrong for automatically jumping to that conclusion. Not all teachers, are bad. Some of them really are trying and the students are just acting up. I've had that happen in classes I taught.

Well, I was definitely wrong for jumping to that conclusion then.

[LogainDiabolos]

Well, I was definitely wrong for jumping to that conclusion then.

Can't blame you. You are right when you say that most teachers are the source of the problem. When you can get a masters or doctorate in Education and become a teacher, there is a fundamental flaw in the system. I mean currently most teachers are the people that couldnt hack it in grad school, or couldn't get a proper research grant. Why are we letting our children be taught by these failures?

I want to learn from people that make the subject their life work. Only then will we get the quality of education the rest of the civilized world has.

[Woozie]

Can't blame you. You are right when you say that most teachers are the source of the problem. When you can get a masters or doctorate in Education and become a teacher, there is a fundamental flaw in the system. I mean currently most teachers are the people that couldnt hack it in grad school, or couldn't get a proper research grant. Why are we letting our children be taught by these failures?

I want to learn from people that make the subject their life work. Only then will we get the quality of education the rest of the civilized world has.

I can't tell if you're being sarcastic or not. If you are, I wasn't trying to say most teachers are failures who couldn't make it anywhere else. Most of the teachers wanted to be teachers every since they were in high school themselves. It doesn't matter why a person is in their field, the wrong attitude will never get you anywhere.

My grandfather who I lived with for years when growing up was a school teacher for years. I've seen all types of different attitudes that different teachers have from seeing him and his friends, from things he's told me, and obviously from personal experience from being in school and from teaching in school.

And yes, there are fundamental flaws in our system, but most of them don't actually come from the teachers. My grandpa had to teach so many classes that he never even got his degree in because the system couldn't afford teachers in the appropriate area. He was a teacher at two different schools at the same freakin time and the conditions under which he had to teach were ridiculous.

Like I said, I could write an entire essay about issues our system has. Many of these do come from the teachers, and many of them are for other reasons.