Answer:
true
Step-by-step explanation:
We are given that sides LM and NM, LO and NO, MO and MO are congruent. Since this describes 3 sides of the triangle, you can say ΔMNO is congruent to ΔMLO. From this, you can say ∠OMN is congruent to ∠OML. The two angles (∠OMN and ∠OML) form a straight line, meaning they add up to 180 degrees. We can write:
∠OMN + ∠OML = 180
And since ∠OMN = ∠OML, we can substitute and solve:
∠OMN + ∠OMN = 180
2∠OMN = 180
∠OML =∠OMN = 90
Since both these angles are 90 degrees, LN is perpendicular to MO by definition.
