DAX for matrix table

Combined SQL Fail Rate =
VAR BaseTable =
ADDCOLUMNS(
VALUES('JIRA_Refined_Data'[checking_parent]),
"TotalChecks", [Total Number of Checks],
"SQLNoFeedback", [Total SQL No Feedback],
"SQLFeedback", [Total SQL Feedback],
"FailRate", [SQL Fail Rate]
)

VAR AvgNoFeedback =
AVERAGEX(
FILTER(
BaseTable,
[TotalChecks] > 0 && [SQLNoFeedback] > 0
),
[FailRate]
)

VAR AvgFeedback =
AVERAGEX(
FILTER(
BaseTable,
[TotalChecks] > 0 && [SQLFeedback] > 0
),
[FailRate]
)

VAR AvgBoth =
AVERAGEX(
FILTER(
BaseTable,
[TotalChecks] > 0 && [SQLNoFeedback] > 0 && [SQLFeedback] > 0
),
[FailRate]
)

RETURN
ROUND(AvgNoFeedback + AvgFeedback - AvgBoth, 2)