How to apply Like Operator in SSRS expression.

HI All,

I have SSRS report, in that i have 2 columns like Account_Code , Variance_Column.

i wants to write expression like

if Account_Code  starts with 4 then i need to multiply variance_column * 1

if Account_Code  starts with 5 ,6 then i need to multiply variance_column * -1

else Same values should appear.

Please do need full.

bala krishna