Question

$\Delta ABC\cong \Delta DEF$ by ASA congruence condition. Find the value of $x$.

• A. $x=20$
• B. $x=30$
• C. $x=40$
• D. $x=50$

Answer 1

The correct option is B $x=30$

We know $\Delta ABC\cong \Delta DEF$ by ASA congruence.
Therefore, $\angle B=\angle F$
$\Rightarrow 60=x+30$
$\Rightarrow x=60-30$
$\Rightarrow x=30$