Question 323550
There is a linear relation in both plans between
Earnings/month = (flat wages)/month + (commission earned/month)
given:
plan A:
{{{E = 900 + .1s}}}
plan B: 
{{{E = 1200 + .15*(s - 8000)}}}
The 2nd term doesn't come into play until {{{s > 8000}}}, otherwise
Stan would be penalized if sales were less than $8000
The question is: when is {{{E}}} the same under both plans?
{{{900 + .1s = 1200 + .15*(s - 8000)}}}
{{{900 + .1s = 1200 + .15s - 1200}}}
{{{.05s = 900}}}
{{{s = 18000}}}
When sales are over $1800, plan B is better
I can plot these plans with {{{E}}} = vertical axis in thousands of dollars
and {{{s}}} = horizontal in thousands of dollars
{{{ graph( 500, 500, -1, 25, -1, 4, .9 + .1x,  .15x  ) }}}