Answer:
![\angle BAC = 141\frac{3}{7} ^{\circ}](https://tex.z-dn.net/?f=%5Cangle%20BAC%20%3D%20141%5Cfrac%7B3%7D%7B7%7D%20%5E%7B%5Ccirc%7D)
Step-by-step explanation:
The interior angle of a regular heptagon = = 900/7° = 128.57°
Therefore, angle DAB = 128.57°
The interior angle of the square = 90°
Therefore, angle DAC = 90°
Therefore, we have
angle DAB+ angle DAC + angle BAC = 360° (sum of angles at a point (A))
Angle BAC = 360° - angle DAB - angle DAC = 360° - 900/7° - 90° = 990/7°
Angle BAC = 141.43°
Expressing 141.43° as a common fraction gives;
![141.43 ^{\circ}= \dfrac{990}{7} ^{\circ}=141\frac{3}{7} ^{\circ}](https://tex.z-dn.net/?f=141.43%20%5E%7B%5Ccirc%7D%3D%20%5Cdfrac%7B990%7D%7B7%7D%20%20%5E%7B%5Ccirc%7D%3D141%5Cfrac%7B3%7D%7B7%7D%20%5E%7B%5Ccirc%7D)
![\angle BAC = 141\frac{3}{7} ^{\circ}](https://tex.z-dn.net/?f=%5Cangle%20BAC%20%3D%20141%5Cfrac%7B3%7D%7B7%7D%20%5E%7B%5Ccirc%7D)