Step-by-step explanation:
The formula of the slope of a line that passes through points (x1, y1) and (x2, y2) is:
![m=(y_1-y_2)/(x_1-x_2)](https://img.qammunity.org/2023/formulas/mathematics/college/fimp7zvgzwrq4ecowqytytl3ydbrfr5mz1.png)
For this problem the slope is:
![m=(-4-(-4))/(5-(-1))=(-4+4)/(5+1)=(0)/(6)=0](https://img.qammunity.org/2023/formulas/mathematics/college/o09dabs3hfzor0vv3mazfcjfbksgo7zumo.png)
A slope of zero indicates that the line is horizontal. Therefore it is a constant.
The slope-intercept form of the equation of a line is:
![y=mx+b](https://img.qammunity.org/2023/formulas/mathematics/high-school/smsb8cbft03lwblmi49nf2l6jby2ofxzws.png)
Where m is the slope and b is the y-intercept. In this case, the slope is zero so we just have:
![y=b](https://img.qammunity.org/2023/formulas/mathematics/college/hakg9nmcvyzasj9povd793j4rdxx4wcogs.png)
b is the y-coordinate of the given points: b = -4
Answer:
y = -4