Given:
The three exterior angles of a pentagon measures 60,80 and 90.
To find:
The measure of other two exterior angle, assuming them equally.
Solution:
Let x be the measure of two other exterior angles of the pentagon.
We know that the sum of all exterior angles of a pentagon is 360 degrees.
![60^\circ+80^\circ+90^\circ+x+x=360^\circ](https://img.qammunity.org/2022/formulas/mathematics/high-school/ar97do32qbf4hmcqgo00jl2p6q5annvdsg.png)
![230^\circ+2x=360^\circ](https://img.qammunity.org/2022/formulas/mathematics/high-school/gcjrfe1cdf6hpdmzuqm4f502mc3wuq3kf0.png)
![2x=360^\circ-230^\circ](https://img.qammunity.org/2022/formulas/mathematics/high-school/jw9l0hywzwp64lfhdmqemphatiech8xroi.png)
![2x=130^\circ](https://img.qammunity.org/2022/formulas/mathematics/high-school/r66ut7wdc5nx8j99nnusgupgmmki6j2rj6.png)
Divide both sides by 2.
![(2x)/(2)=(130^\circ)/(2)](https://img.qammunity.org/2022/formulas/mathematics/high-school/szdg3rdjxfsvctxk5y86u1a8sqnbgp3iw6.png)
![x=65^\circ](https://img.qammunity.org/2022/formulas/mathematics/high-school/ycz03wol8fq2gm5gatirrwk7dqj96ql3vx.png)
Therefore, the measures of both exterior angles are 65 degrees.