
The equation of a elipse:

The length of the major axis is equal 2a if a > b or 2b if b > a.
We have

therefore the length of the major axis is equal 2 · 7 = 14.
-8 and +8 equal 0 since they cancel out. It's basically 8-8. So that leaves you with 0-(-7). The two negatives make a positive, now you're left with 0+7=7. Your answer is 7. Hope this helps :)
Answer:
67.64
Step-by-step explanation:
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