Question

Give the points (4,2) and (-4,6). What is the equation of the line in slope intercept form?

Answer 1

Slope-intercept form: y = mx + b (m is the slope, b is the y-intercept or the y value when x = 0 ---> (0, y))

To find the slope(m), you use the slope formula:

`m=(y_2-y_1)/(x_2-x_1)` And plug in the two points

(x₁ , y₁) = (4, 2)

(x₂ , y₂) = (-4, 6)

`m=(6-2)/(-4-4)`

`m=(4)/(-8)`

`m=-(1)/(2)`

`y=-(1)/(2)x+b` To find b, plug in either of the two points into the equation

(4, 2)

`2 = -(1)/(2)(4)+b`

2 = -2 + b Add 2 on both sides to get b by itself

4 = b

`y = -(1)/(2)x+4`