G

Guest

Guest
Hi folks,

This is my first post so please accept my aplologies if it's not quite right.

I'm doing a basic maths course, but this one equation is driving me mad. I know the answer is 2.8 by typing it in to a equation solver, and it resolves correctly, however I just can see how it's worked out.

y=0.25t^2-2t+4 were y=0.36

If some kind person could offer some help, I'd be very grateful.

Alan

galactus

Super Moderator
Staff member
Subtract .36 from both sides. This gives you the quadratic:

$$\displaystyle \L\\\frac{1}{4}t^{2}-2t+\frac{91}{25}=0$$

Now solve using the quadratic formula. There will be two solutions. $$\displaystyle \L\\\frac{14}{5}$$ is just one of them.

TchrWill

Full Member
Hi folks,
This is my first post so please accept my aplologies if it's not quite right.
I'm doing a basic maths course, but this one equation is driving me mad. I know the answer is 2.8 by typing it in to a equation solver, and it resolves correctly, however I just can see how it's worked out.
y=0.25t^2-2t+4 were y=0.36
If some kind person could offer some help, I'd be very grateful.
Alan

For y = .36 we end up with .25t^2 - 2t + 3.64 or t^2 - 8t + 14.56.

t = [8+/-sqrt(64 - 58.24)]/2
t = [8+/-sqrt(5.76)]/2
t = [8 +/-2.4]/2 = 10.46/2 = 5.2 or 5.6/2 = 2.8

G

Guest

Guest
Thanks for these folks, but can you go into a little more detail. Sorry I feel really thick, I just don't get it....

Sorry to be a bother.

Alan

stapel

Super Moderator
Staff member
amcdee said:
...can you go into a little more detail.
The tutors listed the steps to use, gave the formula to use, and then displayed the use of said formula. That is, they provided the fully-worked solution. What more "detail" were you needing?

Eliz.

G

Guest

Guest
I'm sorry I just don't understand. As I said I'm sorry to be a bother.

I thank those that have taken the trouble / time to reply. Hopefully one day it will make sense. Guess my best bet, is to talk to my tutor(s).

Eliz, I got the impress that my request for further explaination / detail, has irritate you. For that I'm sorry, I'm just trying to get my head round this and struggling.

Wishing you all, all the best.

Kindest regards,

Alan[/list][/quote]

stapel

Super Moderator
Staff member
amcdee said:
Eliz, I got the impress that my request for further explaination / detail, has irritate you.
It is to be regretted that you came to that conclusion. My post meant only what it said: with a fully-worked solution having been provided, it is difficult to see where to add any additional information. So your stating where, specifically, you were stuck would have been helpful.

I apologize for the confusion.

Eliz.

TchrWill

Full Member
i folks,
This is my first post so please accept my aplologies if it's not quite right.
I'm doing a basic maths course, but this one equation is driving me mad. I know the answer is 2.8 by typing it in to a equation solver, and it resolves correctly, however I just can see how it's worked out.
y=0.25t^2-2t+4 were y=0.36
If some kind person could offer some help, I'd be very grateful.