The sum of the two expressions is 6x -4r -4
From the question,
We are to determine the sum of -4r +1 and 6x - 5.
That is, -4r +1 + 6x - 5
The sum of the two expressions can calculated as shown below
-4r +1 + 6x - 5
Collecting like terms, we get
-4r + 6x - 5 +1
Simplifying
-4r + 6x -4
6x -4r -4
Hence, the sum of the two expressions is 6x -4r -4
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