SOLUTION: What is the equation of a line that passes through points (-1, 2) and (5, 2)?

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Question 632514: What is the equation of a line that passes through points (-1, 2) and (5, 2)?
Found 2 solutions by jim_thompson5910, lenny460:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

First let's find the slope of the line through the points and


Note: is the first point . So this means that x%5B1%5D=-1 and y%5B1%5D=2.
Also, is the second point . So this means that x%5B2%5D=5 and y%5B2%5D=2.


m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 Start with the slope formula.


m=%282-2%29%2F%285--1%29 Plug in y%5B2%5D=2, y%5B1%5D=2, x%5B2%5D=5, and x%5B1%5D=-1


m=%280%29%2F%285--1%29 Subtract 2 from 2 to get 0


m=%280%29%2F%286%29 Subtract -1 from 5 to get 6


m=0 Reduce


So the slope of the line that goes through the points and is m=0


Now let's use the point slope formula:


y-y%5B1%5D=m%28x-x%5B1%5D%29 Start with the point slope formula


y-2=0%28x--1%29 Plug in m=0, x%5B1%5D=-1, and y%5B1%5D=2


y-2=0%28x%2B1%29 Rewrite x--1 as x%2B1


y-2=0x%2B0%281%29 Distribute


y-2=0x%2B0 Multiply


y=0x%2B0%2B2 Add 2 to both sides.


y=0x%2B2 Combine like terms.


y=2 Simplify


So the equation that goes through the points and is y=%2B2


Notice how the graph of y=2 goes through the points and . So this visually verifies our answer.
Graph of y=%2B2 through the points and

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Answer by lenny460(1073) About Me  (Show Source):
You can put this solution on YOUR website!
What is the equation of a line that passes through points (-1, 2) and (5, 2)?
(-1,2)
(5,2)
We must find the slope first.
(y2 - y1)/(x2 - x1)
(2 - 2)/(5 - (-1)
2 - 2 = 0
5 - (-1) = 5 + 1 = 6
0/6 = 0
The Slope (m) = 0
To find the equation of line we now use
the point slope formula.
y - y1 = m(x - x1)
We take the coordinates (-1,2)
y - 2 = 0(x - (-1)
x - (-1) = x + 1
0(x + 1)
0 * x = 0x
0 * 1 = 0
Therefore:
y - 2 = 0x
Add 2 to each side of the equation.
y - 2 + 2 = 0x + 2
Combine like like terms:
-2 + 2 = 0
0x + 2 = 2
y = 2

y = 2 is a horizontal line.
A horizontal line has zero slope.



Lennox Obuong
Algebra Student
Email: obuong3@aol.com