(8-t)^2-t(t+7), при t= -3/23

(8-t)²-t(t+7)=64-16t+t²-t²-7t=64-23t, если t= [latex]- \frac{3}{23} [/latex], то [latex]64-23*(- \frac{3}{23} )=64+3=67.[/latex]