Answer:
The other coordinate is (-6,19)
Step-by-step explanation:

(4,-7)
(x,y)
[(4+x)/2 , (-7+y)/2] = (-1,6)
(4 + x)/2 = -1
 4 + x = -2
 × = -6
(-7 + y)/2 = 6
 -7 + y = 12
 y = 19
(Correct me if i am wrong)
 
        
             
        
        
        
 (1/2,3)(2,3/4)
slope = (3/4 - 3) / (2 - 1/2) = (3/4 - 12/4) / (4/2 - 1/2) =
(-9/4) / (3/2) = -9/4 * 2/3 = -18/12 = -3/2
        
             
        
        
        
Answer:
I think the answer is B. I could be wrong tho, love.
 
        
             
        
        
        
Answer:
Equilateral Triangle
Side a = 1
Side b = 1
Side c = 1
Angle ∠A = 60° = 1.0472 rad = π/3
Angle ∠B = 60° = 1.0472 rad = π/3
Angle ∠C = 60° = 1.0472 rad = π/3
C=60°B=60°A=60°b=1a=1c=1
Area = 0.43301
Perimeter p = 3
Semiperimeter s = 1.5
Height ha = 0.86603 
Height hb = 0.86603
Height hc = 0.86603
Median ma = 0.86603 
Median mb = 0.86603
Median mc = 0.86603
Inradius r = 0.28868 
Circumradius R = 0.57735 
Vertex coordinates: A[0, 0] B[1, 0] C[0.5, 0.86603]
Centroid: [0.5, 0.28868]
Inscribed Circle Center: [0.5, 0.28868]
Circumscribed Circle Center: [0.5, 0.28868]
Step-by-step explanation:
 
        
             
        
        
        
It is 40.682414698, or about 40.7 feet of string.