(1)x^2/16-y^2/9=1或y^2/16-x^2/9=1
(2)a=6,c=7,可得b=sqr(13),方程为y^2/36-x^2/13=1
(3)由题意可设a=5t b=3t 求得c=sqr(34)t=sqr(2) t=1/sqr(17)
方程为17x^2/25-17y^2/9=1
(4)9/a^2-1/a^2=1 得a^2=8 方程为x^2/8-y^2/8=1
(1)x^2/16-y^2/9=1或y^2/16-x^2/9=1
(2)a=6,c=7,可得b=sqr(13),方程为y^2/36-x^2/13=1
(3)由题意可设a=5t b=3t 求得c=sqr(34)t=sqr(2) t=1/sqr(17)
方程为17x^2/25-17y^2/9=1
(4)9/a^2-1/a^2=1 得a^2=8 方程为x^2/8-y^2/8=1