(2t-2)(5t+3)-(3t-1)(3t+2)=-4
(10t^2-6t-10t-6)-(9t^2-6t-3t-2)=-4
t^2-19t-4=-4
t^2-19t=0
t(t-19)=0
t=0 и t=19
вроде бы так)