Question

81a-4=0
-16x²=0
-3t²-26=1
(x+5)(x-7)= -35

Answer 1

81a-4=0; a=4/81; a=1/27-16x²=0; x=0
-3t²-26=1; 3t²=-27; t²$neq$-9 (нет корней)
(x+5)(x-7)= -35; x^2-2x-35+35=0; x^2-2x=0; x*(x-2)=0; x1=0; x2=2