Write the slope-intercept form of the equation of line through the given points.

Question

through: (2,1) and (4,-1)

Find the x- and y-intercepts of the equation: y=1/2x-4

Find the x-and y-intercepts of the equation: y=-2x+8

Answer 1

y - y₁ = y₂ - y₁

x - x₁    x₂ - x₁

 

y - 1 = -1 -1 = -2 = -1

x - 2     4 - 2      2 

 

y - 1 = -1

x - 2

y - 1 = -x + 2

y = -x  + 3 

 

y = (1/2)x - 4      In slope-intercept form, y = mx + b, the slope = m and the y-intercept = b.

The y-intercept is -4 or (0,-4).

To find the x-intercept, let y = 0 and solve for x.

0 = (1/2)x - 4

4 = (1/2)x

8 = x or (8,0)

 

y = -2x + 8

The y-intercept is 8 or (0,8)

0 = -2x + 8

-8 = -2x

4 = x or (4,0)