Step by step
The question
Question: solve 12/x + 1 = 4.
First: a bottom can never be 0.
x at the bottom can't be 0.
So x ≠ 0.
1 Remove the fractions
The bottom is x.
Times x will remove it.
We multiply every part by x.
We do it on both sides, so they stay equal.
x divided by x is 1.
x times 1 is x.
x times 4 is 4x.
Write what is left.
No more fractions!
2 Get x on one side
There is x on both sides.
We want x on one side only.
So we remove the x from the left side.
To remove x, we take away x.
We do it on both sides, so they stay equal.
+ x and − x make zero.
Cross them out.
4x − x = 3x.
Now we have 12 = 3x.
Let's swap the two sides, so x is on the left.
3 Remove the 3
3x means 3 times x.
We want just x.
To remove times 3, we divide by 3.
We do it on both sides, so they stay equal.
3 divided by 3 is 1.
So just x is left.
12 divided by 3 is 4.
So x = 4!
4 Check
Let's check: put 4 in place of x.
First the left side.
Now the right side.
Both sides are 4.
So x = 4 is right!
Let's look back.
First: remove the fractions.
Then: get x on one side.
Then: remove the 3.
Last: check.