Follow above:
In the second equation, let x=y-(7/y)
so u get the first equation by substitution of x
..which u have solved already..
so
y-(7/y)=2/3
and y-(7/y)= -6
two more quadratics for you to solve!
(multiply throughout by y)
Hi Guys
Im stuck on the following question
3x^2+16x-12=0 hence solve 3(y-(7/y))^(2)+16(y-(7/y))-12=0
I can get the factors (3x-2) and (x+6) for the first one and so x=2/3 x= -6
its the second part im stuck on
any help would be great please
Thanks
Pete
Ok... now lets try to make things clear:
first of all there were two equations, first one which u already solved and found two values of x.
The second equation ie the one that contains y, requires a bit of common sense.
If you write both equations on paper in maths form, you will notice that the second one
just has y-(7/y) instead of x.
So... your first step will be to solve the second equation for y-(7/y).
Look, if you change x for z in the first equation, doesn't matter, does it?
So similarly u r just using y-(7/y) instead of x. But you already did that in the first equation.
And thats where you get the two new equations
y-(7/y)=2/3
and y-(7/y)= -6
But your objective of the second equation is NOT to find y-(7/y) which is x. It is to find y. It is these two new equations that u now need to solve, forget the original second equation, because these two equations are parts of the second one.