Factorise :
`ab + bc + ax + cx`

Answer

To factorise the expression \( ab + bc + ax + cx \), we can follow these steps:

### Step 1: Group the terms
We can group the terms in pairs to make it easier to factor. Let's group the first two terms and the last two terms:
\[ (ab + ax) + (bc + cx) \]

### Step 2: Factor out the common factors in each group
Now, we will factor out the common factors from each group:
- In the first group \( ab + ax \), the common factor is \( a \):
\[ a(b + x) \]
- In the second group \( bc + cx \), the common factor is \( c \):
\[ c(b + x) \]

So, we can rewrite the expression as:
\[ a(b + x) + c(b + x) \]

### Step 3: Factor out the common binomial factor
Now, we see that \( (b + x) \) is common in both terms, so we can factor that out:
\[ (b + x)(a + c) \]

### Final Answer
Thus, the factorised form of the expression \( ab + bc + ax + cx \) is:
\[ (b + x)(a + c) \]

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