If the focus coordinates of hyperbola y ^ 2 / A ^ 2-x ^ 2 / b ^ 2 = 1 are F1, F2, the length of chord AB passing through F1 is 6, the perimeter of triangle abf2 is 28, e = 5 / 4, find a If the focus coordinates of hyperbola y ^ 2 / A ^ 2-x ^ 2 / b ^ 2 = 1 are F1, F2, the length of chord AB passing through F1 is 6, the perimeter of triangle abf2 is 28, and E = 5 / 4, find the value of a and B

If the focus coordinates of hyperbola y ^ 2 / A ^ 2-x ^ 2 / b ^ 2 = 1 are F1, F2, the length of chord AB passing through F1 is 6, the perimeter of triangle abf2 is 28, e = 5 / 4, find a If the focus coordinates of hyperbola y ^ 2 / A ^ 2-x ^ 2 / b ^ 2 = 1 are F1, F2, the length of chord AB passing through F1 is 6, the perimeter of triangle abf2 is 28, and E = 5 / 4, find the value of a and B

The length of string AB is 6, the circumference of triangle abf2 is 28, and F2a + f2b = 22
（F2A-F1A）+（F2B-F1A）=22-6=16
4a=16
a=4
e=5/4 c=5 b=3
[[not clear, ask again; satisfied, good luck to you!]]