Find the gradient of the line passing through the points P(1, 1) and Q(2, 5).

A.
3 
B.
2 
C.
5 
D.
4
Correct Answer: Option D
Explanation
Let (x_{1}, y_{1}) = (1, 1) and (x_{2}, y_{2})= (2, 5)
then gradient m of (bar{PQ}) is
m = (frac{y_2 – y_1}{x_2 – x_1}) = (frac{5 – 1}{2 – 1})
= (frac{4}{1})
= 4