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

User Jonasberg
by
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2 Answers

6 votes

Answer:

y=mx+b

y=-4x +12 is your equation

m= yo

your slope

Explanation:

User Joyeon
by
5.9k points
4 votes

Answer:

The equation of the line that passes through the points (-1,8) and (2,-4) is:


  • y=-4x+4

Explanation:

Given the points

  • (-1,8)
  • (2,-4)


\mathrm{Slope\:between\:two\:points}:\quad \mathrm{Slope}=(y_2-y_1)/(x_2-x_1)


\left(x_1,\:y_1\right)=\left(-1,\:8\right),\:\left(x_2,\:y_2\right)=\left(2,\:-4\right)


m=(-4-8)/(2-\left(-1\right))


m=-4

As the point-slope form of the line equation is


y-y_1=m\left(x-x_1\right)

where m is the slope.

substituting the values m = -4 and the point (-1,8)


y-\(8\right=-4\left(x-\left(-1\right)\right)


y-8 = -4(x+1)

Add 8 to both sides


y-8+8=-4\left(x+1\right)+8


y=-4x+4

Therefore, the equation of the line that passes through the points (-1,8) and (2,-4) is:


  • y=-4x+4
User Jnemecz
by
5.6k points