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What is an equation of the line that passes through the points (4,-1) and (8,5)?

User Emning
by
5.3k points

1 Answer

9 votes

Answer:

y=3/2x-7

Explanation:

the equation of the line for slope-intercept form is y=mx+b, where m is the slope and b is the y intercept.

we are given two points: (4,-1) and (8,5)

the equation for slope is (y2-y1)/(x2-x1)

label the points:

x1=4

y1=-1

x2=8

y2=5

now substitute into the equation:

m=(5--1)/(8-4)

m=6/4

m=3/2

the slope of the line is 3/2

here is our equation so far:

y=3/2x+b

we need to find b

since the equation will pass through the points, we can substitute either one into the equation to find b

let's use (4,-1) as an example

substitute into the equation

-1=3/2(4)+b

-1=6+b

-7=b

the y intercept is -7

so the equation is y=3/2x-7

hope this helps!

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