=(D-64)2
We move all terms to the left:
-((D-64)2)=0
We calculate terms in parentheses: -((D-64)2), so:
(D-64)2
We multiply parentheses
2D-128
Back to the equation:
-(2D-128)
We get rid of parentheses
-2D+128=0
We move all terms containing D to the left, all other terms to the right
-2D=-128
D=-128/-2
D=+64
150 because 6 times 5 is 30 then you multiply whats inside the square root thing so you'd get 25, 25 is a perfect square which simplifies to 5 then 5 times 30 is 150.
The triangle is an Obtuse triangle
By definition, the number
is the ratio between the circumference and the diameter:

This implies that

And so your circumference is 
Answer:
D. 43°
Step-by-step explanation:
interior angle to 90°=90°
interior angle to 133°=47°
p=180°-47°-90°=43°
please mark as brainliest