Answer:
-11/10 or -1.1
Explanation:
To start, let's get rid of those pesky decimals by multiplying everything by 2. Then we get 9 + 20r = -13. Now, let's isolate the r by subtracting 9 from both sides to get 20r = -22. Finally, we need to divide everything by 20 to get r = -11/10 or -1.1.