Question

x[0.25x+(0.25x+8)]=39.5解方程怎么做？要过程！急！

x[0.25x+(0.25x+8)]=39.5解方程怎么做？要过程！

Answer 1

x[0.25x+(0.25x+8)]=39.5
解 x(0.5x+8)=39.5
0.5x²+8x=39.5
5x²+80x-395=0
△=b²-4ac
=80²-4×5×395
=6400-7900
=-1500
∵△﹤0
∴方程无实根