Answer:
r= -189
Explanation:
You subract the 8 both sides: -13= r/9+8
Which equals to: -21= r/9
In order to get the 9 off, you have to cancel it by multiplying ( opposite of is multiplying) both sides:
9(-21)= r
And the final answer is: r= -189
You can check it by plugging in -189 to r and it works:)
Your welcome:)))