PLEASE HELP, need this is detail.

Answer:
See Below!
Step-by-step explanation:
All you must do to solve the problem is substitute every value of x for the value of 3, therefore it should be as follows:
g(3) = (3)^2 + 3(3)
The answer to this specific question would be: 18, because 3^2 is 9 and 3(3) = 9, so 9+9 = 18
Hope this helps!
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