Question

Line AB passes through points A(–6, 6) and B(12, 3). If the equation of the line is written in slope-intercept form, y = mx + b, then m = – and b = .

Answer 1

The formula of a slope:

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

We have the points A(-6, 6) and B(12, 3). Substitute:

`m=(3-6)/(12-(-6))=(-3)/(18)=-(3:3)/(18:3)=-(1)/(6)`

Therefore we have
`y=-(1)/(6)x+b`.

Put the coordinates of the point B to the equation:

`3=-(1)/(6)(12)+b`

`3=-2+b` add 2 to both sides

`5=b\to b=5`

Answer:

`m=-(1)/(6)\\\\b=5`