Question has missing figure, the figure is in the attachment.
Answer:
The measure of ∠1 is 65°.
The measure of ∠2 is 65°.
The measure of ∠3 is 50°.
The measure of ∠4 is 115°.
The measure of ∠5 is 65°.
Step-by-step explanation:
Given,
We have an isosceles triangle which we can named it as ΔABC.
In which Length of AB is equal to length of BC.
And also m∠B is equal to m∠C.
ext.m∠C= 115°(Here ext. stands for exterior)
We have to find the measure of angles angles 1 through 5.
Solution,
For ∠1.
∠1 and ext.∠C makes straight angle, and we know that the measure of straight angle is 180°.
So, we can frame this in equation form as;
On putting the values, we get;
![\angle 1+115\°=180\°\\\\\angle1=180\[tex]\therefore m\angle2=65\°](https://tex.z-dn.net/?f=%5Cangle%201%2B115%5C%C2%B0%3D180%5C%C2%B0%5C%5C%5C%5C%5Cangle1%3D180%5C%5Btex%5D%5Ctherefore%20m%5Cangle2%3D65%5C%C2%B0)
-115\°=65\°[/tex]
Thus the measure of ∠1 is 65°.
For ∠2.
Since the given triangle is an isosceles triangle.
So, 
Thus the measure of ∠2 is 65°.
For ∠3.
Here ∠1, ∠2 and ∠3 are the three angles of the triangle.
So we use the angle sum property of triangle, which states that;
"The sum of all the angles of a triangle is equal to 180°".
Now we put the values and get;
Thus the measure of ∠3 is 50°.
For ∠4.
∠4 and ∠2 makes straight angle, and we know that the measure of straight angle is 180°.
So, we can frame this in equation form as;
Substituting the values of of angle 2 to find angle 4 we get;
Thus the measure of ∠4 is 115°.
For ∠5.
∠4 and ∠5 makes straight angle, and we know that the measure of straight angle is 180°.
So, we can frame this in equation form as;
Substituting the values of of angle 4 to find angle 5 we get;
Thus the measure of ∠5 is 65°.
Hence:
The measure of ∠1 is 65°.
The measure of ∠2 is 65°.
The measure of ∠3 is 50°.
The measure of ∠4 is 115°.
The measure of ∠5 is 65°.
