Question 1101660
<br>Technically, you need to specify, in the statement of the problem, that LN is the base, so that LM and MN are the two congruent sides.<br>
Then, since T is the midpoint of LN, segments LT and NT are congruent.
And of course segment MT is congruent to itself.<br>
So then you can prove the triangles congruent using SSS.