Question

Can you please mildly explain this with the answer.

Answer 1

$\bf \begin{cases} f(x)=&5x-1\\ f(-3)=&5(-3)-1\\ f(-3)=&-15-1\\ f(-3)=&-16 \end{cases}\qquad \begin{cases} g(x)=&2x^2+1\\ g(-3)=&2(-3)^2+1\\ g(-3)=&2(-3)(-3)+1\\ g(-3)=&2(9)+1\\ g(-3)=&18+1\\ g(-3)=&19 \end{cases} \\\\[-0.35em] ~\dotfill\\\\ (f\times g)(-3)\implies f(-3)\times g(-3)\implies (-16)(19)\implies -304$