Answer:
[tex]y=40\°[/tex]
Step-by-step explanation:
we know that
An isosceles triangle has two equal sides and two equal angles
The two equal angles are called the base angles and the third angle is called the vertex angle
In this problem the triangle ABC is an isosceles triangle
so
[tex]AB=AC[/tex]
[tex]5x=40\°[/tex]
[tex]x=8\°[/tex]
The sum of the internal angles of a triangle is equal to [tex]180\°[/tex]
so
Find the value of y
[tex](2y+20)\°+2(40\°)=180\°[/tex]
[tex]2y=180\°-20\°-80\°[/tex]
[tex]2y=80\°[/tex]
[tex]y=40\°[/tex]
