Need a quick answer please

Which of the fallowing best completes the sequence 12,8,5, a) 1 b) 2 c)4 d)0

Atriangle with all sides of equal length is a/an triangle. a. right b. scalene c. equilateral d. isosceles

Use the formulas a = x 2 – y 2, b = 2xy, c = x 2 + y 2 to answer this question. one leg of a right triangle has length 11 and all sides are whole numbers. find the lengths of the other two sides. the other leg = a0 and the hypotenuse = a1