Question

A is the point with coordinates (4,6)

B is the point with coordinates (d,21)
the gradient of the line AB is 3
work out the value of 3

Answer 1

d = 9

Explanation:

In this question, we are asked to calculate the value of d , given the coordinates and the slope of the line.

Mathematically, the slope of the line could be calculated using the formula

m = (y2 -y1)/(x2 - x1)

Now, let’s say (x1,y1) = (4,6)

and (x2, y2) = (d, 21)

and our n from the question is 3.

Let’s insert all these into the equation;

3 = (21-6)/(d -4)

3(d-4) = 15

3d - 12 = 15

3d = 15 + 12

3d = 27

d = 27/3

d = 9