Question 952538
You probably hit a mental block when you could "see" it was x=10:
30-x=-4x Add 4x to each side
30+3x=0 Subtract 30 from each side
3x=-30 Divide each side by 3.
x=-10
CHECK:
5-1/6(-10)=-2/3(-10)
5+(10/6)=20/3
(30/6)+(10/6)=40/6
40/6=40/6