Answer: x = 12
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Step-by-step explanation:
Points Z and Y are midpoints of segments SR and RQ respectively.
These points form the midsegment ZY.
SQ is twice as long compared to YZ, since the midsegment is half as long as the side parallel to it.
We can then say...
SQ = 2*(YZ)
3x-8 = 2*(x+2)
3x-8 = 2x+4
3x-2x = 4+8
x = 12