#(t-3)/6-(t-25)/5=4#
#:.(5(t-3)-6(t-25)=120)/30#
#:.(5(t-3))/30-(6(t-25))/30=120/30#
multiply #color(red)( L.H.S and R.H.S. by 30#
#:.30/1 xx ((5(t-3))/30-(6(t-25))/30=120/30) xx 30/1#
#:.cancel30^color(red)1/1 xx (5(t-3))/cancel30^color(red)1-cancel30^color(red)1/1 xx (6(t-25))/cancel30^color(red)1=cancel30^color(red)1/1 xx 120/cancel30^color(red)1#
#:.color(red)1/color(red)1 xx (5(t-3))/color(red)1-color(red)1/color(red)1 xx (6(t-25))/1=color(red)1/color(red)1 xx 120/color(red)1#
#:.5(t-3)-6(t-25)=120#
#:.5t-15-6t+150=120#
#:.5t-6t-15+150=120#
#5t-6t+135=120#
#-t=120-135#
#:.-t=-15#
multiply #color(red)( L.H.S and R.H.S. by -1#
#:.t=15#
check:
substitute #color(red)( t=15#
#:.((color(red)15)-3)/6-((color(red)(15)-25))/5=4#
#:.12/6-((-10))/5=4#
#:.12/6+10/5=4#
#:.2+2=4#