Answer:
m∠ABC = 81°
m∠FEC = 90°
Explanation:
A median of a triangle is a line segment from the vertex to the mid-point of the side opposite that vertex.
If AB ≅ BC then triangle ABC is an isosceles triangle.
Therefore, if BE is the median of triangle ABC, then m∠ABE ≅ m∠CBE.
Therefore, the measure of ∠ABC is twice the measure of ∠ABE.
First, convert the given measure of ∠ABE into decimal degrees.
![\boxed{\textsf{Decimal degrees}=\sf Degrees + (Minutes)/(60)+ (Seconds)/(3600)}](https://img.qammunity.org/2023/formulas/mathematics/college/76p80khxj76qwntkmac6jrdo274lu4jej0.png)
![\begin{aligned}\implies \angle ABE=40^(\circ)30'&=40+(30)/(60)+(0)/(3600)\\&=40+0.5+0\\&=40.5^(\circ)\end{aligned}](https://img.qammunity.org/2023/formulas/mathematics/college/uzd9x560clr5nc4k82xl56j20str4i5ovf.png)
Therefore, m∠ABE = 40.5°.
If m∠ABC is twice the measure of ∠ABE:
![\begin{aligned}\implies m \angle ABC&=2 * \angle ABE\\&=2 * 40.5^(\circ)\\&=81^(\circ)\end{aligned}](https://img.qammunity.org/2023/formulas/mathematics/college/7fur80n93lz179li47dqfmddmjdcxu27q8.png)
As triangle ABC is an isosceles triangle where AB≅BC, the median BE is perpendicular to AC. Therefore, m∠FEC = 90°.