Answer:
B is your correct answer.
Step-by-step explanation:
[tex]a^{2} +b^{2} =c^{2} \\a=15\\b=6x-3\\c=24\\\\15^{2} + (6x-3)^{2} =24^{2} \\225+(6x-3)^{2} =576\\(6x-3)^{2} =801\\\\\sqrt{(6x-3} =\sqrt{801}\\\\(6x-3)= 28.301\\6x= 31.301\\x=5.216[/tex]