More = Addition
"Twice a Number" = Multiplication (specifically by two)

Since the order of operations tell us to multiply before we add, we can simplify

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Answer:
So F(x+3) = (x+3+5)/2 = (x+8)/2
Step-by-step explanation:
Given F(2x-1) = x+2
Put 2x-1 = y=> x = (y+1)/2
Hence F(y) = (y+1)/2 +2 = (y+5)/2
So F(x) = (x+5)/2
So F(x+3) = (x+3+5)/2 = (x+8)/2.
A. If you disassemble the shapes and add the numbers, you can get the answer :).