Answer: The correct option is (A) 7.
Step-by-step explanation: Given that the triangles ABC and DEF are similar to each other.
We are given to find the value of x from the figure.
We note from the figure that
in triangles ABC and DEF, AB = 30 units, BC = 42 units, DE = 5 units and EF = ?
Since the two triangles are similar, so their corresponding sides ae proportional.
Therefore, we must have
[tex]\dfrac{AB}{DE}=\dfrac{BC}{EF}\\\\\\\Rightarrow \dfrac{30}{5}=\dfrac{42}{x}\\\\\\\Rightarrow 6=\dfrac{42}{x}\\\\\Rightarrow x=\dfrac{42}{6}\\\\\Rightarrow x=7.[/tex]
Thus, the required value of x is 7.
Option (A) is CORRECT.
