Answer:
13.7
Step-by-step explanation:
A{2} + B{2} =C{2} \\
6{2} +B{2} =15{2} \\
6x6+B(2) =15x15\\
36+B(2)=225\\
-36\\
\sqrt{189} =13.7
The third option
4×3 - 3×2 -2x + 11
6:8