Solving a problem in physics section 1 point 54 optics

Solving a problem in physics section 1 point 54 optics

54. Two plane mirrors are arranged at an angle to each other and placed between a point source of light. The distance from this source to a mirror 3 cm to the other - 8 cm. The distance between the first image in the mirror 14 cm. Find angle β (degrees) between the mirrors.

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Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)