Factorization of Polynomial or expression-
`xa + ya + xz + yz`

Answer

To factor the polynomial \( xa + ya + xz + yz \), we can follow these steps:

### Step 1: Group the terms
We can group the terms in pairs to make it easier to factor:
\[ (xa + ya) + (xz + yz) \]

### Step 2: Factor out the common factors from each group
In the first group \( xa + ya \), we can factor out \( a \):
\[ a(x + y) \]
In the second group \( xz + yz \), we can factor out \( z \):
\[ z(x + y) \]

So, we rewrite the expression as:
\[ a(x + y) + z(x + y) \]

### Step 3: Factor out the common binomial factor
Now, we notice that \( (x + y) \) is a common factor in both terms:
\[ (x + y)(a + z) \]

### Final Result
Thus, the factorization of the polynomial \( xa + ya + xz + yz \) is:
\[ (x + y)(a + z) \]

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