The form of the linear equation is
![y=mx+b](https://img.qammunity.org/2023/formulas/mathematics/high-school/smsb8cbft03lwblmi49nf2l6jby2ofxzws.png)
m is the slope
b is the y-intercept
Since the slope of the line is 1, then
m = 1
Substitute it in the form of the equation above
![\begin{gathered} y=(1)x+b \\ y=x+b \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/1rlluwo6k7z73twl957u40yfqseeg5klko.png)
To find b substitute x and y in the equation by the coordinates of a point on the line
Since the line contains the point (4, 1), then put
x = 4 and y = 1
![1=4+b](https://img.qammunity.org/2023/formulas/mathematics/college/b0vt5iyux3nhawmevzxu6euhgs7bgs0jmg.png)
Subtract 4 from both sides to find b
![\begin{gathered} 1-4=4-4+b \\ -3=b \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/6qzkcvm41jn79wbsv0p3godkorh303de0x.png)
Substitute the value of b in the equation
![\begin{gathered} y=x+(-3) \\ y=x-3 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/1p6lecy1oesp1p8fb45ob7p8dov3h0uyxi.png)
The equation of the line is y = x - 3