Answer: -85
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Step-by-step explanation:
from 5 to 3 is "minus 2"
from 3 to -1 is "minus 4"
from -1 to -7 is "minus 6"
from -7 to -15 is "minus 8"
and so on
Keep up this pattern to get the next five terms
-15 - 10 = -25
-25 - 12 = -37
-37 - 14 = -51
-51 - 16 = -67
-67 - 18 = -85
So the tenth term is -85