The slope would be 58.
Slope = (change in y) / (change in x)
That relationship is established by the fixed cost of each ticket ($58). The handling fee is a constant that would shift the curve upward by $5, but would have no effect on the slope of the line since it is completely independent from the number of tickets being purchased (x).
The reciprocal should be the number flipped...
in this case..

is the reciprocal.
Total cost: 148 x 79.5 = 11,766
7% of 11,766 = 11,766 x 7 = 82.362/100 = 823,62
so, his commision was of 823,62
The given expression is

THe given expression is a rational expression, and rational expression should not have 0 in the denominator.
Moreover, the denominator is a square root term, and square root don't have a value for negative number .
Therefore 2x+10 must be greater then 0. That is

Therefore the required domain in set builder form is
{
}