Answer:
Ab^2 = CA^2 + BC^2
8^2 = 6^2 + a^2
64 = 36 + a^2
64-36 = a^2
28 = a^2
square root of 28 = square root of a^2
5 ,29 = a
5 = a
Through my research I found a question similar to this and found the right description matching answers: so we have to find the perimeter of this: ''Shape ABCD is shown. Point A is at negative 3, 5. Point B is at 1, 7. Point C is at 3, 3. Point D is at negative 1, 1.''
Answer would be C) 17.9
Perimeter is sum of all the sides ,
so, perimeter will be 7 + 9 + x = 16 + x
it will be more than 16 for sure
6 is the answerI equations