change so x is the subject
y=2/x
and
y=-n/x
the minus is for the whole fraction
please show your working
thanks in advance :)
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Well, the way you phrased it now makes it so much easier ...
y = 2/x
multiply by x
xy = 2
divide by y
x = 2/y
do the same for the second part.
To change the subject of the equation, we want to isolate the variable we wish to make the subject. In this case, we want to make x the subject in both equations.
Let's begin with the first equation:
y = 2/x
To make x the subject, we need to get rid of the fraction by multiplying both sides of the equation by x:
yx = 2
Now we can isolate x by dividing both sides of the equation by y:
x = 2/y
So the equation with x as the subject is: x = 2/y.
Moving on to the second equation:
y = -n/x
Since the minus sign (-) is for the whole fraction, we can multiply both sides of the equation by -1 to eliminate it:
-1 * y = -1 * (-n/x)
-y = n/x
Next, we can swap the positions of n and -y:
n = -y * x
Finally, we want to make x the subject, so we'll divide both sides of the equation by -y:
n / (-y) = (-y * x) / (-y)
The -y terms on the right side cancel out, giving us:
n / (-y) = x
Finally, we can simplify the negative sign by multiplying both sides of the equation by -1:
(-1) * (n / (-y)) = (-1) * x
This simplifies to:
-n / y = x
Therefore, the equation with x as the subject is: x = -n/y.
So, the solutions are:
For the first equation: x = 2/y
For the second equation: x = -n/y