Steply

Solve 2x/(x - 1) - 2/(x - 1) = 3

Step by step, with the reason for every step · Rational equations · Algebra 2

Step by step

The question

Question: solve 2x/(x − 1) − 2/(x − 1) = 3.

2xx − 1 − 2x − 1 = 3

First: a bottom can never be 0.

x = 1 makes x − 1 0.

So x ≠ 1.

x ≠ 1

1 Remove the fractions

The bottom is (x − 1).

Times (x − 1) will remove it.

We multiply every part by (x − 1).

We do it on both sides, so they stay equal.

(x − 1) × 2xx − 1 − (x − 1) × 2x − 1 = (x − 1) × 3

(x − 1) divided by (x − 1) is 1.

(x − 1) divided by (x − 1) is 1.

(x − 1) times 3 is 3(x − 1).

Write what is left.

No more fractions!

2x − 2 = 3(x − 1)

2 Open the brackets

The 3 in front of the bracket multiplies every part inside.

So we write 3 times each part.

2x − 2 = 3 × x + 3 × (−1)

Work out each multiplication.

2x − 2 = 3x − 3

3 Get x on one side

There is x on both sides.

We want x on one side only.

So we remove the 2x from the left side.

To remove 2x, we take away 2x.

We do it on both sides, so they stay equal.

2x − 2 − 2x = 3x − 3 − 2x

2x and − 2x make zero.

Cross them out.

3x − 2x = x.

3x − 2x = x

Now we have −2 = x − 3.

−2 = x − 3

Let's swap the two sides, so x is on the left.

x − 3 = −2

4 Remove the − 3

We want x by itself.

The − 3 is in the way.

To remove − 3, we add 3.

We do it on both sides, so they stay equal.

x − 3 + 3 = −2 + 3

− 3 and + 3 make zero.

Cross them out.

−2 + 3 = 1.

−2 + 3 = 1

So x = 1!

x = 1

But x = 1 is the x that is not allowed: it makes a bottom 0.

So there is no solution.

x = 1 makes a bottom 0: no solution.

Let's look back.

First: remove the fractions.

Then: open the brackets.

Then: get x on one side.

Last: remove the − 3.

Answer
x = 1 makes a bottom 0: no solution.

More from Rational equations

The whole lesson: Rational equations →