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
![(AB)/(DE)=(BC)/(EF)\\\\\\\Rightarrow (30)/(5)=(42)/(x)\\\\\\\Rightarrow 6=(42)/(x)\\\\\Rightarrow x=(42)/(6)\\\\\Rightarrow x=7.](https://img.qammunity.org/2019/formulas/mathematics/middle-school/kia7ewzewkc9811rnp8um2r6zmq4rvgojm.png)
Thus, the required value of x is 7.
Option (A) is CORRECT.