Answer: 12.4 inches
Step-by-step explanation:
[tex]c^{2}=a^{2} + b^{2} \\c^{2}=8^{2} + 10^{2}\\\sqrt{c^{2}=164\\[/tex]
c=12.8, c=-12.8
It can not be -12.8 as there's no such thing as a negative length. Therefore the diagonal length of the photo frame is 12.8 inches
