Math Help - angle between bisectors

1. angle between bisectors

The bisectors of the base angles of an isosceles triangle meet at I.
Find the angle between the bisectors at their point of intersection
if the vertex angle is 700

May i know what does this mean?

2. Re: angle between bisectors

$\alpha = \beta = \delta = \gamma$

3. Re: angle between bisectors

it is 125 degrees the angle in the intersection of the 2 base angle bisectors.