A, B, and C are the correct answers. I understand why B and C are correct, but can you explain why A is correct? The explanation says you know the slope of line k is negative because both intercepts have the same sign. I understand the intercepts have the same sign but how does that mean the slope is negative?

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You will have to visualise this on paper.

Hope this explains well:

The y-intercept can either be positive or negative (never 0 because it doesn’t pass the origin)

Case 1: When y-intercept is positive

x intercept will be positive too because x int = 2 ( y int)

Hence, x int would be towards the right of the origin.

Draw a line from +y to +x: the slope is negative, ie value of y is decreasing with increase in x

Case 2: When y-intercept is negative

x intercept will be negative too because x int = 2 ( y int)

Hence, x int would be towards the left of the origin.

Draw a line from -y to -x: the slope is negative, ie value of y is decreasing with increase in x

Hence, A is correct

Thank you!