Question

Help me with this please anyone x

Answer 1

$\bf \begin{array}{cccccclllll} \textit{something}&&\textit{varies directly to}&&\textit{something else}\\ \quad \\ \textit{something}&=&{{ \textit{some value}}}&\cdot &\textit{something else}\\ \quad \\ y&=&{{ k}}&\cdot&x \\ && y={{k }}x \end{array}\\\\ -------------------------------$

$\bf \textit{we know that }\qquad \begin{cases} y=42\\ x=6 \end{cases}\implies 42=k6\implies \cfrac{42}{6}=k \\\\\\ 7=k\impliedby \textit{constant of variation} \\\\\\ thus\qquad \qquad y=7x \\\\\\ \textit{what is "y" when x=5?}\qquad y=7(5)\impliedby \textit{solve for "y"} \\\\\\ \textit{what is "x" when y=28?}\qquad 28=7x\impliedby \textit{solve for "x"}$