One of my MGMAT books shows
1/2z - 1/x ==> x-2z/2xz.
I believe this is a very basic step where you "multiply through" with "xz", or something, but I just don't see it for some reason. Can anyone out there break down how exactly this step is done?
Thanks!
Mutilplying Through
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To subtract fractions, the denominators need to be the same.
so the original problem is:
1/2z - 1/x
The common denominator for these two fractions is 2xz
So to give the first fraction a denominator of 2xz, you need to multiply the numerator and denominator by x. This will leave us with x/2xz.
To give the second fraction a denominator of 2xz, you need to multiply the numerator and denominator by 2z. This will leave us with 2z/2xz
Now we have:
x/2xz - 2z/2xz
Now because the two fraction have a common denominator, we can combine the numerator. Once you combine the numerator, you are left with:
x-2z/2xz
so the original problem is:
1/2z - 1/x
The common denominator for these two fractions is 2xz
So to give the first fraction a denominator of 2xz, you need to multiply the numerator and denominator by x. This will leave us with x/2xz.
To give the second fraction a denominator of 2xz, you need to multiply the numerator and denominator by 2z. This will leave us with 2z/2xz
Now we have:
x/2xz - 2z/2xz
Now because the two fraction have a common denominator, we can combine the numerator. Once you combine the numerator, you are left with:
x-2z/2xz