Answer:
9
Step-by-step explanation:
Value of 'a' = 15
Value of 'b' = 6
Simplifying the expression given in question,
[tex]9a^{2} -48ab+64b^{2}[/tex]
[tex]=> (3a)^{2} - 2*3a*8b+(8b)^{2}[/tex]
[tex]=>(3a-8b)^{2}[/tex]
Putting 'a' & 'b' in above expression ,
[tex](3a-8b)^{2} = (3*15-8*6)^{2} = (45-48)^{2} = (-3)^{2} =9[/tex]
