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Write an equation of the line that passes through the pair of points.
(-5,-4), (5,-3)

Write an equation of the line that passes through the pair of points. (-5,-4), (5,-3)-example-1
User Andrewmitchell
by
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1 Answer

15 votes
15 votes

Explanation:

the most common form of line equation is

y = ax + b

a is the slope of the line. it is expressed as the ratio

y coordinate change / x coordinate change

when going from one point to the other.

b is the y-intercept (the y value when x = 0).

once we have the slope, we get b by using the coordinates of one of the given points as x and y in the equation and since for b.

for the slope a :

x changes by +10 (from -5 to 5)

y changes by +1 (from -4 to -3)

the slope is +1/+10 = 1/10

the equation looks now like

y = (1/10)x + b

let's use the first point.

-4 = (1/10)×-5 + b = -1/2 + b

-3 1/2 = -7/2 = b

the equation is

y = (1/10)x - 7/2

so, the second answer option is correct.

User Vivek Doshi
by
2.6k points