Find the missing length of the right triangle.

20, because by using Pythagorean theorem, a2+b2=c2. Let’s make a=12 and b=16. (12)2 + (16)2 =c2. If you simplify this, 144 + 256 = c2. 144 + 256 = 400, so 400=c2. Finally if we take the square root of both sides, c=20.

Best answer that i found on yahoo ok   set :   x= length of 2nd piece in cm  x- 3= length of 1st piece in cm  x-4= length of 3rd piece in cm  then since you know they all came from the 20 cm ribbon you add them together and set them equal to 20x+ x-3 +x-4 = 20  3x - 7= 20  3x= 27  x= 9  the shortest piece is the third piece which is x- 4  x-4  9-4 = 5  the length of the smallest piece is 5 cm.  the other lengths are  9 cm  6 cm