I would like to have a formula that will add together data from two different worksheets. The below SUMPRODUCT formula works well for finding the data with two criteria on one sheet but I need a way to combine the two formulas together so the result would be the total from the both formulas.

Hope this make sense! Thank you for any and all help

SUMPRODUCT(--(Sheet1!$A2:$A10000=$A3),--( Sheet1!$B2:$B10000=B$1),--( Sheet1!$C2:$C10000))
SUMPRODUCT(--(Sheet2!$A2:$A10000=$A3),--( Sheet2!$B2:$B10000=B$1),--( Sheet2!$C2:$C10000))

example:
SUMPRODUCT(--(Sheet1!$A2:$A10000=$A3),--( Sheet1!$B2:$B10000=B$1),--( Sheet1!$C2:$C10000))+SUMPRODUCT(--(Sheet2!$A2:$A10000=$A3),--( Sheet2!$B2:$B10000=B$1),--( Sheet2!$C2:$C10000))