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What is the length of PR?

Answer-
The length of PR is 7 units.
Solution-
Given,
in the ΔDEF,
m∠D = 25°, m∠E = 114°, DF = 21, DE = 15
in the ΔPQR,
m∠P = 25°, m∠Q = 114°, PR = x, PQ = 5
So, ΔDEF ~ ΔPQR by AA (Angle-Angle) similarity, as
So, according to similarity
[tex]\Rightarrow \dfrac{DF}{PR}=\dfrac{DE}{PQ}=\dfrac{EF}{QR}[/tex]
Putting the values,
[tex]\Rightarrow \dfrac{21}{x}=\dfrac{15}{5}[/tex]
[tex]\Rightarrow x=\dfrac{21\times 5}{15}[/tex]
[tex]\Rightarrow x=7[/tex]