SOLUTION: Indicate in standard form the equation of the line passing through the given points, writing the answer in the equation box below. E ( - 2, 2), F (5, 1)

Algebra ->  Points-lines-and-rays -> SOLUTION: Indicate in standard form the equation of the line passing through the given points, writing the answer in the equation box below. E ( - 2, 2), F (5, 1)       Log On


   



Question 1206892: Indicate in standard form the equation of the line passing through the given points, writing the answer in the equation box below.
E ( - 2, 2), F (5, 1)

Found 3 solutions by MathLover1, Theo, josgarithmetic:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Finding the Equation of a Line
First lets find the slope through the points (-2,2) and (5,1)


m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 Start with the slope formula (note: (x%5B1%5D,y%5B1%5D) is the first point (-2,2) and (x%5B2%5D,y%5B2%5D) is the second point (5,1))


m=%281-2%29%2F%285--2%29 Plug in y%5B2%5D=1,y%5B1%5D=2,x%5B2%5D=5,x%5B1%5D=-2 (these are the coordinates of given points)


m=+-1%2F7 Subtract the terms in the numerator 1-2 to get -1. Subtract the terms in the denominator 5--2 to get 7



So the slope is

m=-1%2F7





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Now let's use the point-slope formula to find the equation of the line:




------Point-Slope Formula------
y-y%5B1%5D=m%28x-x%5B1%5D%29 where m is the slope, and (x%5B1%5D,y%5B1%5D) is one of the given points


So lets use the Point-Slope Formula to find the equation of the line


y-2=%28-1%2F7%29%28x--2%29 Plug in m=-1%2F7, x%5B1%5D=-2, and y%5B1%5D=2 (these values are given)



y-2=%28-1%2F7%29%28x%2B2%29 Rewrite x--2 as x%2B2



y-2=%28-1%2F7%29x%2B%28-1%2F7%29%282%29 Distribute -1%2F7


y-2=%28-1%2F7%29x-2%2F7 Multiply -1%2F7 and 2 to get -2%2F7

y=%28-1%2F7%29x-2%2F7%2B2 Add 2 to both sides to isolate y


y=%28-1%2F7%29x%2B12%2F7 Combine like terms -2%2F7 and 2 to get 12%2F7 (note: if you need help with combining fractions, check out this solver)



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Answer:



So the equation of the line which goes through the points (-2,2) and (5,1) is:y=%28-1%2F7%29x%2B12%2F7


The equation is now in y=mx%2Bb form (which is slope-intercept form) where the slope is m=-1%2F7 and the y-intercept is b=12%2F7


Notice if we graph the equation y=%28-1%2F7%29x%2B12%2F7 and plot the points (-2,2) and (5,1), we get this: (note: if you need help with graphing, check out this solver)


Graph of y=%28-1%2F7%29x%2B12%2F7 through the points (-2,2) and (5,1)


Notice how the two points lie on the line. This graphically verifies our answer.





y+=+-+%281%2F7%29x%2B12%2F7+....write in standard form Ax+%2B+By=+C, both sides multiply by 7
7y+=+-+x%2B12+
x%2B7y+=+12+

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
the points are (-2,2), (5,1)
let x1,y1 = -2,2 and x2,y2 = 5,1
slope = (y2-y1)/(x2-x1) = (1-2)/(5+2) = -1/7
use one of the points to get the y-intercept.
general slope intercept form equation is y = mx + b
m is the slope
b is the y-intercept
when the slope is -1/7, equation becomes y = -1/7 * x + b
use (5,1) coordinate and replace y with 1 and x with 5 to get:
1 = -1/7 * 5 + b
solve for b to get:
b = 1 + 5/7 = 12/7
equation becomes y = -1/7 * x + 12/7.
that's the slope intercept form of the equation.
to get the standard form, do the following:
add -1/7 * x to both sides of the equation to get 1/7 * x + y = 12/7
multiply both sides of the equation by 7 to get x + 7y = 12
that's the standard form of the equation.

here's the graph.



note that the standard form and the slope intercept form of the equation draw the same line.
that's because they're equivalent.

the two speciied points are on the line.
they are (-2,2) and (5,1)
the slope intercept is (0,1.714) where 1.714 represents the fraction 12/7.

Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Through (-2,2) and (5,1) as ax+by=c

Point-Slope form
y-1=%28%281-2%29%2F%285-%28-2%29%29%29%28x-5%29
y-1=-%281%2F7%29%28x-5%29
7y-7=-%28x-5%29
7y-7=-x%2B5
7y%2Bx=12
highlight%28x%2B7y=12%29