Answer:
r=2
Step-by-step explanation:
r + 11 + 8r = 29
add the like terms
r+8r+11=29
9r+11=29
then subtract 11 on both sides to eltimate 11
9r=18
lastly divide 9 on both sides
r=2
 
        
                    
             
        
        
        
Answer:
enter t= 12
Step-by-step explanation:
I think it helps
 
        
                    
             
        
        
        
It can go up to four dimensional.
        
             
        
        
        
Instead of negative positive and instead of positive negative hope you get it right. Am not that smart
        
             
        
        
        
From the given information, we get the value of ABC = 120°.
<h3>How to estimate the value of ABC?</h3>
Given: In the figure, O exists the center of the circle and OABC exists as a parallelogram.
Now, the radius of the circle exists 
OA = OB = OC 
Opposite sides of a parallelogram are equal
AB = OC and OA = BC
In ∆OAB,
OA = OB = AB and,
In ∆OCB,
OC = OB = BC
Therefore, ∆OAB and ∆OCB exist in equilateral triangles.
All angles of an equilateral triangle are equivalent to 60°.
Hence, ∠ABC = ∠OBA + ∠OBC
∠ABC = 60° + 60°
∠ABC = 120° 
Therefore, the value of ∠ABC = 120°.
To learn more about parallelogram refer to:
brainly.com/question/24291122
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