1: are you serious ?

2: why is there no TZ^2 term in equation(2) ?

3: have you tried setting T=0, thus (as example) equation(1) becoming:

7145.3X^2 - 19700Y^2 = 489

I guess you could rewrite each equation in terms of T, thus getting 4 equalities,

but only a deeply troubled mathematician would try that