Method I used:
We are given the hypotenuse and the perimeter. Thus, we can use this to our advantage, because note that we not only know the sum of the other two sides, which is the perimeter-hypotenuse, but we also have the Pythagorean theorem. We can use the Pythagorean theorem to derive a quadratic equation we can use to then solve for the length of our sides, which I've done so below:
$a+b+c\quad =\quad 14\\ a+b\quad =\quad 8,\quad since\quad 14-c\quad =\quad 8\\ Let\quad a\quad =\quad 8-b\\ { (8-b) }^{ 2 }+{ b }^{ 2 }={ 6 }^{ 2 }\\ 64-16b+{ b }^{ 2 }+{ b }^{ 2 }=36\\ 64-16b+{ 2b }^{ 2 }=36\\ 28-16b+2{ b }^{ 2 }=0$
$28-16b+2{ b }^{ 2 }=0\\ 2{ b }^{ 2 }-16b+28=0\\ 2({ b }^{ 2 }-8b+14)=0\\ { b }^{ 2 }-8b+14=0\\ a=1,b=-8,c=14\\ \frac { 8\pm \sqrt { 64-4*14 } }{ 2 } =\frac { 8\pm \sqrt { 8 } }{ 2 } =4\pm \sqrt { 8 } ;\quad $
$\frac { 8\pm \sqrt { 64-4*14 } }{ 2 } =\frac { 8\pm \sqrt { 8 } }{ 2 } =4\pm \sqrt { 8 } ;\quad \\ If\quad b=4+2\sqrt { 2 } ,\\ a=8-b,\therefore a=8-(4+2\sqrt { 2 } )=4-2\sqrt { 2 } \\ If\quad b=4-2\sqrt { 2 } ,\\ a=8-b,\therefore a=8-(4-2\sqrt { 2 } )=4+2\sqrt { 2 } \\ \therefore (a,b)\quad =\quad (4-2\sqrt { 2 } ,4+2\sqrt { 2 } )\\ 1/2bh\quad =\quad 1/2a*b=1/2(4-2\sqrt { 2 } )(4+2\sqrt { 2 } )\\ \\ \\ \\ \\ \\ \\ $
If you simplify the above expression, you will get the area (which is 4).