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Simultaneous equations

mind helping me out?


there's 2 I'm struggling with (solve the simultaneous equations):

1. x+y=2 and x^2+2y^2=11


2. 3y-x+6 and 4x^2+9y^2=36


Taken from my AS level bridging course booklet, if anyone's wondering.
(edited 9 years ago)
I wish I could do maths (just about do GCSE if I'm lucky)...

Some YouTube resources if struggling with the concept: https://www.youtube.com/watch?v=Lwto-lQzmec
Reply 2
Original post by mickel_w
mind helping me out?


there's 2 I'm struggling with (solve the simultaneous equations):

1. x+y=2 and y=x^2+2y^2=11


2. 3y-x+6 and 4x^2+9y^2=36


Taken from my AS level bridging course booklet, if anyone's wondering.


Don't mess around with the complicated expressions, rearrange the linear ones for x or y and substitute into the complex ones, simplify and you'll probably form a quadratic for the values of x or y, then resubstitute the values you get back into the linear equations to get the corresponding x or y coordinates...
Did that help?

Posted from TSR Mobile
Reply 3
And the second equation in 1. has two = signs. Shouldn't one be a +?
Reply 4
Original post by lamp-y
And the second equation in 1. has two = signs. Shouldn't one be a +?


oops, fixed


Original post by hellodave5
I wish I could do maths (just about do GCSE if I'm lucky)...

Some YouTube resources if struggling with the concept: https://www.youtube.com/watch?v=Lwto-lQzmec


no examples like this :frown:


Original post by TLHroolz
Don't mess around with the complicated expressions, rearrange the linear ones for x or y and substitute into the complex ones, simplify and you'll probably form a quadratic for the values of x or y, then resubstitute the values you get back into the linear equations to get the corresponding x or y coordinates...
Did that help?

Posted from TSR Mobile


yes it did actually, thank you :smile:

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