Answer:
B. 0
Explanation:
The slope of a straight horizontal line is always equal to 0.
To support the above statement, we can show working out:
m = slope of the line
m = ( y1 - y2 ) / ( x1 - x2 )
Two points on line = ( 0 , - 2 ) , ( 1 , - 2 )
y1 = - 2
y2 = - 2
x1 = 0
x2 = 1
m = [ ( - 2 ) - ( - 2 ) ] / [ ( 0 ) - ( 1 ) ]
m = ( - 2 + 2 ) / ( 0 - 1 )
m = 0 / - 1
m = 0
The y values on a horizontal line will always be the same. When calculating the subtraction of y values in the numerator of the formula for the slope of a line, a number subtracted by itself will always equal to 0. 0 divided by any number will always equal to 0. Hence, the slope of a straight horizontal line will always equal to 0.