Question 106997
The slope intercept form is 

{{{y=mx+b}}}

Since the line passes through (1,5), we can use the values {{{x=1}}} and {{{y=5}}}
And, the slope, m, is equal to -1,

Solving for b,

{{{y=mx+b}}}
{{{5=-1(1)+b}}}
{{{5=-1+b}}}
{{{5+1=-1+1+b}}}
{{{6=0+b}}}
{{{b=6}}}


Thus, the equation is {{{y=-x+6}}}


GRAPH:

{{{graph(1000,1000,-20,20,-20,20,-x+6)}}}


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