Question

What is an equation of the line that passes through the points (-2, 1) and (-8, 4)?

Answer 1

Answer:   y =  - ¹/₂ x    OR  y - 1 = - ¹/₂ (x + 2)  

Step-by-step explanation:  

        For us to write the equation for this line, we need to (1) find the slope of the line, and (2) use one of the points to write an equation:  

       The question gives us two points, (-2, 1) and (-8, 4), from which we can find the slope and later the equation of the line.

Finding the Slope  

The slope of the line (m) = (y₂ - y₁) ÷ (x₂ - x₁)    

                                         =  (4 - 1) ÷ (-8 - (-2))  

                                         =   - ¹/₂  

Finding the Equation  

We can now use the point-slope form (y - y₁) = m(x - x₁)) to write the equation for this line:

                                 ⇒  y - 1 =   - ¹/₂ (x - (-2))

                                  ∴  y - 1 = - ¹/₂ (x + 2)

  we could also transform this into the slope-intercept form ( y = mx + c)  

                                   since  y - 1 = - ¹/₂ (x + 2)

                                           ⇒     y =  - ¹/₂ x  

       

To test my answer, I have included a Desmos Graph that I graphed using the information provided in the question and my answer.