What, if anything, is wrong with using the formula -SUM(A2+B2+C2) in cell D2 in order to compute the sum of the numbers in row 2? fx -SUM(A2+B2+C2) D2 C E 1 |=SUM(A2+B2+C2) 2 12 15 |18 3 4 It is an error. The SUM function requires 2 or more arguments. =SUM(A2+B2+C2) has just one argument. O It will work, but it's not the most efficient. If you want to use the SUM function you should use -SUM(A2:C2). If you want to add the numbers individually, you should use =A2+ B2+C2. When you use SUM(A2+B2+C2), Excel adds the three numbers and passes the result to the function SUM which returns the result you passed it. Nothing. SUM(A2+B2+C2) is the best formula for computing the sum of the numbers in row 2 You should use absolute rather than relative cell references