Cubic Equation (1 Viewer)

[Whovian99]

Hey Guys!

So for these two equations:

y=80-x^2
y=20-(162.5/x)

Other than graphically, is there a way to solve this algebraically? And if there is, how do I do it?

Thanks!

 

[Paradoxica]

Hey Guys!

So for these two equations:

y=80-x^2
y=20-(162.5/x)

Other than graphically, is there a way to solve this algebraically? And if there is, how do I do it?

Thanks!

Well, there is the cubic formula....

But no, there is no way to solve the given system of equations using HSC techniques and knowledge.

 

[davidgoes4wce]

Have you learnt the rational roots theorem?

 

[Whovian99]

No, could you explain it to me?

 

[leehuan]

http://www.wolframalpha.com/input/?t=crmtb01&f=ob&i=y=80-x^2,+y=20-162.5/x These solutions look just ugly. Are you sure you were told to solve that in 2U

 

[tywebb]

Hey Guys!

So for these two equations:

y=80-x^2
y=20-(162.5/x)

Other than graphically, is there a way to solve this algebraically? And if there is, how do I do it?

Thanks!

Here is what I get by using the cubic formula at http://users.tpg.com.au/nanahcub/cubic.gif
(by first rearranging it to solve x³-60x-162.5=0):



It looks somewhat better in this form than the one you get from wolframalpha.

 

[eyeseeyou]

Find the x and y intercepts and graph it in the form of a cubic equation

 

[Nailgun]

Find the x and y intercepts and graph it in the form of a cubic equation

pls stop saying random things lel

 

[eyeseeyou]

pls stop saying random things lel

How am I posting random stuff?