The slope is the ratio of Change in height to the change in horizontal distance. It can also be define as tangent of angle made by that line and it is find by formula,
The slope is said to be a positive slope when a line is moving from left to right, the line rises.
The slope is said to be a negative slope when a line is moving from left to right, the line falls.
Here, Let the student earns be y marks in test
and let incorrect question be x
then y₁ = 98 , y₂ = 90 and x₁ = 1 , x₂ = 5
⇒ m = -2
Hence, it has negative slope.