Question

PLEASE HELP!!!!!

The vertex angle of an isosceles triangle is 40 degrees less than the sum of the measures of the base angles. Determine the measure of the vertex angle.

Answer 1

Let the base angles be x as both are equal in a isosceles triangle
Now, x+x+(x-40)=180. Since sum of angles of a triangle
2x+(2x-40)=180
2x+2x-40=180
4x=180+40
4x=220
x=220/4
x=55

Now,they asked us vertex angle which is 40 degrees less than sum of base angles
Therefore x+x-40=vertex angle
2x-40=vertex angle
2(55)-40=vertex angle
110-40=vertex angle
Vertex angle =70 degrees

Answer 2

◆ Triangles ◆

Hey !!

Check the attachment.

Hence , the Vertex measures 70°
Hope it helps you :)