Answer:
is the expression which is equivalent to
.
In other words:

Step-by-step explanation:
Given the expression

solving





∴ 
Thus,

Therefore,
is the expression which is equivalent to
.
Answer:
7r³ - 3r² + 20r
Step-by-step explanation:
(9r³ + 5r² + 11r) + (-2r³ + 9r - 8r²)
You can get rid of the parentheses since there is nothing to distribute.
9r³ + 5r² + 11r - 2r³ + 9r - 8r²
Combine like factors.
7r³ - 3r² + 20r
Answer:
it would be 20 I'm not 100 percent tho