Dear Keke,
First, sketch yourself the triangle, making sure that <D is obtuse.Can we call the unknown angle Angle E? Label the vertices of the triangle.
Let's determine the measure of Angle E.
Since the angles of ALL triangle add up to 180:
180 – (m<D + m<F) = m<E
180 — (110 + 38) = m<E
180 — 148 = m<E
32 = m<E
m<D = 110
m<E = 32
m<F = 38
The LONGEST side of the triangle is opposite the LARGEST angle. The SHORTEST side of the triangle is oppose the SMALLEST angle.
I do not like to do my students' homework for them. However, this gives you enough information to finish your assignment. By the way, you will call the sides DE, EF, and DF with a little line segment along the top of each.