Syllabus Question: 8t^2=1-10t (1 Viewer)

[sazlik]

[Solved] Syllabus Question: 8t^2=1-10t

I'm using the syllabus to make some notes for myself and 1.4(iii) has an example question I can't make sense of. The section is 'quadratic equations, including solution by factorisation and by formula' and the question is .

As far as I can tell, there's no straightforward solution to that question—it's left me a bit puzzled. I ran it through WolframAlpha and it says that
or .

So what is this? XD Is it a typo, or am I missing something really obvious in trying to solve this question?

 

[SeCKSiiMiNh]

I'm using the syllabus to make some notes for myself and 1.4(iii) has an example question I can't make sense of. The section is 'quadratic equations, including solution by factorisation and by formula' and the question is .

As far as I can tell, there's no straightforward solution to that question—it's left me a bit puzzled. I ran it through WolframAlpha and it says that
or .

So what is this? XD Is it a typo, or am I missing something really obvious in trying to solve this question?

8t^2 + 10t - 1 = 0

t = -10 +- root(132)/16
t = -10 +- 2 root(33) / 16

by quadratic formula

 

[ohexploitable]

The section is 'quadratic equations, including solution by factorisation and by formula' and the question is .

I think you're meant to solve using the quadratic formula?

 

[NewiJapper]

using the quadratic formula i got...



EDIT: SeCKSiiMiNh! Same answer, hi five! haha

 

[AAEldar]

using the quadratic formula i got...



EDIT: SeCKSiiMiNh! Same answer, hi five! haha

Yea, you simplify it so that it becomes 2root33, then you can cancel down.

 

[NewiJapper]

Sorry for being lazy ^^

 

[SeCKSiiMiNh]

using the quadratic formula i got...



EDIT: SeCKSiiMiNh! Same answer, hi five! haha

lol just "minh" should suffice

 

[AAEldar]

Sorry for being lazy ^^

Haha, well usually you lose marks if you don't cancel down to simplest form

 

[hscishard]

You can factorise via the quadratic formula.
Just make sure you use the negative of them.

[Quad formula solves it. E.g. You get the answers 2, -1. Factorised is (x-2)(x+1)]

 

[sazlik]

Oh, of course, I'm such an idiot! XD Cannot believe I had to ask.

Thanks guys.

 

[t00l]

Oh, of course, I'm such an idiot! XD Cannot believe I had to ask.

Thanks guys.

someones gonna do well in ext2 math

 

[sazlik]

someones gonna do well in ext2 math

Oh, shoosh! XD