Question 1009660
This is a linear equation. All linear equations look
like: {{{ y = m*x + b }}}
{{{ m }}} is the slope of this straight line 
{{{ b }}} is the y-intercept of the line
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You have: {{{ y = .05x + 2000 }}}
{{{ m = .05 }}} This is the slope.
{{{ b = 2000 }}} This is the y-intercept
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(a)
The slope corresponds to the 5% commission rate
(b)
The y-intercept occurs where {{{ x = 0 }}}, so this
is what he earns per month when he makes no sales
and just earns his base salary
(c)
{{{ y = .05x + 2000 }}}
{{{ x = 10000 }}}
{{{ y = .05*10000 + 2000 }}}
{{{ y = 500 + 2000 }}}
{{{ y = 2500 }}}
His monthly salary is $2,500
(d)
{{{ 3500 = .05x + 2000 }}}
{{{ .05x = 1500 }}}
{{{ x = 30000 }}}
He must have $30,000 in sales
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Here's the plot:
{{{ graph( 400, 400, -5, 40, -1, 5, .05x + 2 ) }}}
The scale of both axes is in thousands of dollars