Like terms have same variables

Unlike terms have different variables

Let’s look at some examples

###
**
2𝑥, 3𝑥
**

2𝑥 & 3𝑥 have the same variable 𝑥

So they are like terms

###
**
3𝑥
**
^{
2
}
**
y, 2y𝑥
**
^{
2
}

3x
^{
2
}
y has variable 𝑥
^{
2
}
y

2yx
^{
2
}
has variable y𝑥
^{
2
}
i.e 𝑥
^{
2
}
y
*
(As x
*
^{
2
}
*
y = y𝑥
*
^{
2
}
*
)
*

So, they are like terms

###
**
−4𝑥y, 3xy
**

−4𝑥y has variable 𝑥y

3𝑥y has variable 𝑥y

−4xy and 3xy have same variable xy.

So, they are like terms.

###
**
4𝑥y, 3𝑥
**

4𝑥y has variable 𝑥y

3𝑥 has variable 𝑥

4𝑥y, 3𝑥 have different variables.

So, they are unlike terms.

###
**
21z, 39z
**

21z has variable z

39z has Variable z

21z and 39z has same variable z

So, they are like terms.

###
**
8, 9
**

Since both 8 & 9 do not have a variable

∴ They are like terms