4^{3x -9} - 10 = -343x−9−10=−3
4^{3x -9} = 743x−9=7 //add 10 to both sides
3x -9 = log_(4) 73x−9=log47 //log_4log4 on both sides (log_a(a^{x})=xloga(ax)=x)
3x = log_4(7) + 93x=log4(7)+9 //add 9 to both sides
x = {log_4(7) + 9}/3x=log4(7)+93 //divide both sides by 3