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y is inversely proportional to x for positive values. When x = 3.5, y = 4.2 Work out the value of y when x = 5.6​

2 Answers

8 votes
  • x1y1=x2y2
  • 3.5(4.2)=(5.6)Y2
  • 14.7=5.6y2[/tex]
  • y2=2.6

y has value 2.6

User Anurag Sharma
by
7.7k points
8 votes

Answer:

y = 2.625

Explanation:

If y is inversely proportional to x for positive value:


y \propto (1)/(x)\implies y=(k)/(x)\quad \textsf{for some constant }k, k > 0


\begin{aligned}\textsf{when }x=3.5, y=4.2 \implies 4.2 & =(k)/(3.5)\\k & = 4.2 \cdot 3.5\\k & = 14.7\end{aligned}


\textsf{Therefore }y=(14.7)/(x)


\begin{aligned}\textsf{when }x=5.6\implies y & =(14.7)/(5.6)\\y & = 2.625\end{aligned}

User Cugomastik
by
7.2k points