From the lines represented in the graph in the given question, line a has a slope of -2.
Slope of the line:
Let us write the standard equation for a straight line as given below:
y = mx + c
where m is the slope of the line.
According to the question, the slope of the line must be -2, so that:
y = -2x + c
or
y + 2x = c = constant
for line a:
at x = 0 , y = -2, so:
-2 + 0 = c ⇒ c = -2
now, at y = 0 , x = -1, so:
0 - 2 = c ⇒ c = -2
It gives the same value of c for both the intercepts, therefore line a has a slope of -2.
Learn more about slope of a line:
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