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Answer: 0.5
Step-by-step explanation:
Given
Line passes through [tex](-10,-30), (0,-25), (10,-20), \text{and}\ (20,-15)[/tex]
The slope of the line is
[tex]m=\dfrac{y_2-y_1}{x_2-x_1}[/tex]
Taking any two points: (0, -25) and (20,-15)
Slope is
[tex]\Rightarrow m=\dfrac{-15-(-25)}{20-0}=\dfrac{10}{20}\\\\\Rightarrow m=0.5[/tex]