I believe it is 15 I am using trigonometry but I’m not 100% sure
The function for a is (f o g) (x) = 8x^2-10.
Explanation
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I already knew that the g of x is equal to

so I substitute inside of the g of x

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simplify it

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Answer: B
Step-by-step explanation:
The line is curved which makes it a non-linear function.
log(3x) = log(2x-4)
taking antilog of both sides:
3x = 2x - 4
3x - 2x = -4 [subtracting 2x from both sides]
x = -4
and we're done already!