Recall that the slope-intercept form of the equation of a line is as follows:
![\begin{gathered} y=mx+b, \\ where\text{ m is the slope of the line and \lparen0,b\rparen is the y-intercept.} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/h6if317flnrpz1tfn9yelfjrabtbjkpio5.png)
Also, the standard form of the equation of a line is as follows:
![\begin{gathered} Ax+By=C, \\ Where\text{ A, B, and C are integers and A>0.} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/zzvjpi0fbrbcpawk3f75ey9c5bcdg4o3w5.png)
Then the slope-intercept form of an equation with slope m=1 is as follows:
![y=x+b.](https://img.qammunity.org/2023/formulas/mathematics/college/t0ut6mw7a1wvtog8caeoeuswnt3pk3htrq.png)
Now, we know that the line passes through (-4,1), then:
![1=-4+b.](https://img.qammunity.org/2023/formulas/mathematics/college/cixq4xxgl9xd9on8gxjwxtwrl3q97ggcsv.png)
Adding 4 to the above equation we get:
![\begin{gathered} 1+4=-4+b+4, \\ 5=b. \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/wuzxpg98xkm8ksbt217o3aghpogtn6ld6j.png)
Therefore the slope-intercept form of the equation that passes through (-4,1) and has a slope of m=1 is:
![y=x+5.](https://img.qammunity.org/2023/formulas/mathematics/college/a2ixn5q4ugmtjl4aqzjtcz0jw233zjdt8x.png)
Adding -y-5 to the above equation we get:
![\begin{gathered} y-y-5=x+5-y-5, \\ -5=x-y. \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/r7y4eval9siniaf57yb5bz4pcp262cn70p.png)
Answer:
![x-y=-5.](https://img.qammunity.org/2023/formulas/mathematics/college/lrasc3rzjit6mealr727sr4goz0810baeg.png)