Identify the terms as like or unlike,
8r , 8r2
To determine if terms are like or unlike, you can begin by writing each term as the product of its numerical coefficient and its variable portion.
8r = 8* r
8r2 = 8*r2
Now look at the variable parts, r and r2. If they are identical including the powers on the variable, then the terms 8r and 8r2 are like terms. Otherwise, they are unlike terms.
The variable parts are not identical because one has an exponent of 2 and the other doesn’t.
Thus, the terms are unlike terms.