Write the scale factor
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Let:
[tex]\begin{gathered} FO\cdot k=QK \\ \end{gathered}[/tex]Where:
k = scale factor
so:
[tex]\begin{gathered} 18k=24 \\ k=\frac{24}{18} \\ k=\frac{4}{3} \end{gathered}[/tex]now, we can find y and x:
[tex]\begin{gathered} \frac{4}{3}\cdot x=28 \\ x=\frac{28\cdot3}{4} \\ x=21 \end{gathered}[/tex][tex]\begin{gathered} 15\cdot\frac{4}{3}=y \\ 20=y \end{gathered}[/tex]