What is g(21) equal to?
g(t) = t-6/3
g(21) = [1]
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You have to plug the given input in the formula: if you substitute t with 21 you have
[tex]g(t) = \dfrac{t-6}{3} \implies t(21) = \dfrac{21-6}{3}=\dfrac{15}{3}=5[/tex]