Step-by-step explanation:
hopefully it makes sense and is visible
:)
We can employ a simple repeated decimal trick:
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Alternatively, we can compute the partial sum of the series.
As , the second term vanishes and we're left with . Notice that this is really just a more formal version of the earlier trick.
Answer:
D
Step-by-step explanation:
What you need to do is find the slope of both lines. Perpendicular lines are the negative inverse of each other. The slope of the lie between points R and F is (2-4)/(1+9)=-1/5. Now you need to find the line where the slop is 5. If you look at D, the slope of the line those points lie on is (25-15)/(4-2)=5 which makes D the answer.