We need to have some choices to give you the answer
-1 + 10 = 9 +10 = 19 + 10 = 29 so the next would be 39 because you add ten to it and there is only one answer with 39 so it's C
Answer:

Step-by-step explanation:
Given
--- equation 1
--- equation 2
Required
Fill in the blank
A linear equation is represented as:

Where m represents the slope
If (1) and (2) are perpendicular, then:

In
--- equation 2

So, we have:



Hence, the complete equation is:

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