Question 666240
{{{(x-10)(2/5)=9x(1/5)}}}

{{{(5/5)(x-10)(2/5)=(5/5)(9x)(1/5)}}}

{{{10(x-10)=5*9x}}}

{{{2(x-10)=9x}}}

{{{2x-20=9x}}}

{{{-20=7x}}}

{{{highlight(-20/7=x)}}}