How do you graph y = | -1/4x -1|?

2 Answers
Dec 4, 2017

graph{abs(-1/4x-1) [-10, 10, -5, 5]}

Explanation:

finding the point when y=0

-1/4x-1=0

then x=-4

when x<=-4

abs(-1/4x-1)=-1/4x-1

when x> -4

abs(-1/4x-1)=1/4x+1

both lines 'll be draw

y=-1/4x-1

finding y-intercept when x=0

y=-1 then the point to ubicate (0,-1)

when y=0
x=-4 the point is (-4,0)

for y=1/4x+1

y-intercept is when x=0
y=1 (0,1)

x-intercept is when y=0
x=-4 (-4,0)

Dec 4, 2017

if x=0 then y=1
if x=-4 then y=0
if x=-8 then y=1 (as well)

Explanation:

Absolute value mirrors everything that is in negative numbers to the positive numbers.
I simply draw a net. Then put instead of x a number. For example:
x=0 then y=1
if x=-4 the y=0
Now you can draw a line that goes through this two points. The other part will be mirrored just like the right side. Let's see.
Let's put instead of x a number -8. Then y=1 just as for the x=0.
Hope it helps.
There is also a way to split this function into two(a bit useless for this particular example).
f_1: y=-1/4x-1 for x>=0
f_2: y=1/4x+1 for x<0
Hope it helps