How can I search an argument in GSheets to return TRUE if the argument references another cell?

Question

Hello! In some cells in the True Price Column, I applied a discount by referencing the cell Conv!C2. For example, the argument in D13 is =MROUND((D8 * 2) * Conv!C2, 5) where (D8 * 2) is me calculating the rate, * Conv!C2 is me applying the discount, and MROUND(,5) is me rounding to the nearest 5. I would like to create argument to calculate the savings. Here's a semi-layman's explanation of what I would like to do:

IF D13's argument references Conv!C2, take the value of D13 before rounding and calculating the discount, in this case $60.00, then subtract the final value of the cell, in this case $55.00. Then return that value as currency. ELSE, leave the cell blank.

E13 should output $5.00.

Answer 1

Okay, I was over-complicating this. If you have a lot of data, the following solution will not work, but since I only had two discounted prices, I can enter some aspects manually.

In order to calculate the value before discount and rounding, I manually entered the argument, (D8 * 2) and subtracted the final value of D13 with the rounding and discount. So the final argument of E13 was =(D8 * 2) - D13.

I still do not know how to search an argument, but my specific situation was solved.