ANSWER
![36](https://img.qammunity.org/2023/formulas/mathematics/college/8cjb0jvbayfo8ijwfanz7hxn5yjn6eqe1q.png)
Step-by-step explanation
Recall, that the sum of interior angles of a regular polygon is calculated using the formula;
![(n-2)180](https://img.qammunity.org/2023/formulas/mathematics/college/bmlzdq16r15560uvbz6uhf5r57hz9xlcx9.png)
Hence, The measure of an interior angle (a) of a regular polygon of n sides is given by:
![a=((n-2)*180)/(n)](https://img.qammunity.org/2023/formulas/mathematics/college/d4teb4l1vrra8v2614hvrr62hrqzvrcbgr.png)
Now, set this equal to 170 and solve;
![170=((n-2)*180)/(n)](https://img.qammunity.org/2023/formulas/mathematics/college/bxocghhnh3300w2e0uq28dr2y7v05q19o3.png)
Multiply both sides by n;
![\begin{gathered} 170n=(n-2)*180 \\ 170n=180n-360 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/hv3zbjzi219o3kdvxwrjww9eedwgqxe6wb.png)
collect like terms;
![\begin{gathered} 170n=180n-360 \\ 360=180n-170n \\ 360=10n \\ 10n=360 \\ n=(360)/(10) \\ =36 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/vu8a77bxa7tc53gqx1jd2q9be5xh1nf076.png)
Therefore, the polygon has 36 sides.