Answer:
[tex]x=14[/tex]
Step-by-step explanation:
Similar shapes have proportional corresponding sides. So,
[tex]\dfrac{AB}{PQ}=\dfrac{BC}{QR}=\dfrac{CD}{RS}=\dfrac{DE}{ST}=\dfrac{EA}{TP}[/tex]
Substitute all lengths:
[tex]\dfrac{4}{28}=\dfrac{3}{21}=\dfrac{5}{35}=\dfrac{3}{21}=\dfrac{2}{x}[/tex]
Therefore,
[tex]\dfrac{2}{x}=\dfrac{1}{7}\\ \\x=14[/tex]
