{2-9[2+(3+1/2)^2]}-4
solve
{2-9[2+(3+1/2)^2]}-4 =
{ 2 - 9 [ 2 + (7/2)^2]} - 4 =
{ 2 - 9 [2 + 49/4) ] } - 4 =
{2 - 9 [ 57/4] } - 4 =
{ 2 - 513/4} - 4 =
{ 8/4 - 513/4 } - 4 =
-505/4 - 4 =
-505/4 - 16/4 =
-521/4 = - [ 130 + 1/4 ]
do this