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13 votes
13 votes
Find the equation of the line formed made by joining the pints (-2,-4),(-8,10)

User Celwell
by
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1 Answer

14 votes
14 votes

Answer:

y = (-7/3)x - 26/3

Explanation:

To find the equation of a line given two points, we can first define an equation of a line to be y= mx +b, with m being the slope and b being the y intercept.

To calculate the slope, we can use the formula (change in y)/(change in x), or

(y₂-y₁)/(x₂-x₁). If we define (-2, -4) as point 1 (meaning -2 is x₁ and -4 is y₁) and (-8, 10) as point 2 (it doesn't matter which point is point 1/2), we can say that the slope is equal to

(10-(-4)) / (-8-(-2)

= 14/(-6)

= -7/3

Therefore, our formula so far is

y = (-7/3)x + b

To figure out b, we can plug in a point, e.g. (-8, 10) and solve for b. Plugging this in, we get

10 = (-7/3)(-8) + b

10 = 56/3 + b

subtract 56/3 from both sides

10 - 56/3 = b

= 30/3 - 56/3

= -26/3

Therefore, our equation is

y = (-7/3)x - 26/3

User Ansil
by
2.5k points