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

1 Answer

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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.

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