whenever y equals 5 this usually means that 5 is the answer because on the Y intercept it usually is just five but if you had x equals 7 the x intercept would be 7 .
The idea is to multiply all sides by 5, then add 1 to all sides
This converts to the interval notation
note: a curved parenthesis means "do not include this value in the solution set"; while a square bracket has us include the value. So we exclude -9 and include 16.