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23 votes
With slope –1/4, passing through (-4, -1)

User Nazli
by
5.6k points

1 Answer

7 votes

Answer:


y = -(1)/(4)x - 2

Explanation:

i'm not sure if you're trying to find the equation of the line ?? but i'll assume that's the case and find the slope-intercept form equation of the line.

slope intercept form is
y = mx + b, where
m is the slope and
b is the y-intercept. since the slope is already identified, you can plug in
-(1)/(4) for
m.


  • y = mx + b
    y = -(1)/(4)x+b

plug in the
x and
y values from the coordinate pair that passes through the line, which is (-4, -1). you can start with either
x or
y, but i'm going to start with
x.

first, plug in
-4 for
x.


  • y = -(1)/(4)x+b
    y = -(1)/(4)(-4)+b

now plug in
-1 for
y.


  • y = -(1)/(4)(-4)+b
    -1 = -(1)/(4)(-4)+b

after plugging in all of the given values, the equation is now
-1 = -(1)/(4)(-4)+b, in which you need to solve for
b.

now it's time to solve! begin by multiplying
-(1)/(4)(-4) in order to simplify the right side of the equation.


  • -(1)/(4)(-4) = 1

you now have
-1 = 1 + b. subtract 1 from both sides of the equation. on the right side, it cancels itself out, leaving you with
b. on the left side of the equation, you now have
-1 - 1, which equals
-2.

therefore
-2 = b, or
b = -2.

now that you've solved for your
b value, plug it into your initial slope-intercept form equation!


  • y = -(1)/(4)x + b
    y = -(1)/(4)x - 2

if you want to check to make sure that the values are correct, plug (-4, -1) into your completed slope-intercept form equation. as you did in the beginning, plug in
-4 for
x and
-1 for
y.


  • y = -(1)/(4)x - 2
    -1 = -(1)/(4)(-4) - 2

begin simplifying by multiplying
-(1)/(4)(-4).


  • -1 = -(1)/(4)(-4) - 2
    -1 = 1 - 2

subtract
1 - 2.


  • -1 = 1 - 2
    -1 = -1

since both sides of the equation are equal, that means your
b value of
-2 is correct because it makes the equation true!

aaaand there you go! i hope this helps. have a great day! <3

User Austin Marshall
by
5.1k points
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