## Intermediate Algebra: Connecting Concepts through Application

$f(g(x))=21x+14$
The student incorrectly found $g(f(x))$ instead of $f(g(x)).$ With $f(x)= 3x-10$ and $g(x)= 7x+8 ,$ then by replacing $x$ with $g(x)$ in $f,$ \begin{array}{l}\require{cancel} f(g(x))=f(7x+8) \\\\ f(g(x))=3(7x+8)-10 \\\\ f(g(x))=21x+24-10 \\\\ f(g(x))=21x+14 .\end{array}