Answer:
Step-by-step explanation:
The formula of a slope:
[tex]m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]
We have two points (-10, 5) and (5, 5).
Substitute:
[tex]m=\dfrac{5-5}{5-(-10)}=\dfrac{0}{15}=0[/tex]
The slope is equal 0. Therefore given line is a horizontal line.