Question

The slope of the line that passes through the point (-9, 3) and (3,21) is which of the following

1) 2/3
2) -2/3
3) 3/2
4) -3/2​

Answer 1

`\displaystyle m=(3)/(2)`

Explanation:

The slope of a Line

Suppose we know the line passes through points A(x1,y1) and B(x2,y2). The slope can be calculated with the equation:

`\displaystyle m=(y_2-y_1)/(x_2-x_1)`

The points are (-9,3) and (3,21), thus:

`\displaystyle m=(21-3)/(3+9)`

`\displaystyle m=(18)/(12)`

Simplifying by 6:

`\mathbf{\displaystyle m=(3)/(2)}`