Answer:
The value of a is 50°.
Explanation:
In an isosceles triangle, 2 sides have the same lengths and same angles so we can assume that the other side of the triangle is 65°.
Given that the total angle of a triangle is 180°, so have to subtract it :
![a = 180 - 65 - 65](https://img.qammunity.org/2021/formulas/mathematics/high-school/oenn4x3rpg9wpte48q56eug25vcwkkcu7j.png)
![a = 180 - 130](https://img.qammunity.org/2021/formulas/mathematics/high-school/exd67kaqi8kvo0i7eidpggxmcfw6dcehf7.png)
![a = 50](https://img.qammunity.org/2021/formulas/mathematics/high-school/htcd269o1eapjrsgofkvaquxw7n9blheyu.png)