Two angles are called supplementary when their measures add up to 180 degrees.
If angles A and B are supplementary, it means that:
![A+B=180](https://img.qammunity.org/2023/formulas/mathematics/college/ghvgspk9x7o1avrb5kcqm1wlaz7tkl21es.png)
If the measure of angle A is 60 degrees larger than twice the of the supplemental angle B, it can be had that:
![A=2B+60](https://img.qammunity.org/2023/formulas/mathematics/college/uhuijhvgdyet4p2b3xxyfmkeng3zlqmitp.png)
Substitute the equation for A into the first equation:
![2B+60+B=180](https://img.qammunity.org/2023/formulas/mathematics/college/s3yp19bclml2padvj1ssk1hc6p4ceqgs96.png)
Solving for B:
![\begin{gathered} 3B+60=180 \\ 3B=180-60=120 \\ \therefore \\ B=(120)/(3) \\ B=40\degree \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/dd9ns285lr63gaojci7hpwb3bwl2mc47jj.png)
The measure of angle A can be gotten by substituting the value of B into the equation for A:
![\begin{gathered} A=2(40)+60 \\ A=80+60 \\ A=140\degree \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/lmk2tldn7h9aumb8devcfuubtkvi1dnims.png)
The measure of A is 140°.