How do you graph and solve #| 5 x + 5 | = 0#?

2 Answers
Tony B
Dec 2, 2015

#x=(-1)#
I have no idea how you would graph this context other than a line parallel to the y-axis that passes through #x=-1# ?????

Explanation:

The value on the right is zero. So what is on the left has to have the same value as zero.

So #|5x+5| -=0#

As far as I can see #x# can only have 1 value and that is #(-1)#
This is because #|0|=0#

and #5xx(-1)+5 = 0#

so #| 5xx(-1)+5 | =0#

Meave60
Dec 2, 2015

#x=-1#
The graph should be v-shaped.

Explanation:

Solving the equation for #x#.

#abs(5x+5)=0#

Remove the absolute value.

#5x+5=0#

Subtract #5# from both sides.

#5x=-5#

Divide both sides by #5#.

#x=(-5)/5#

#x=-1#

Graphing the Equation

#abs(5x+5)=0#

Since the expression inside the absolute value bars can be positive or negative, and we need to graph it, we need to substitute #y# for #0# so we can get points to plot on the graph.

#abs(5x+5)=y#

Now we need to substitute positive and negative values for #x# and solve for #y#.

Table of Points
#x=-3,# #y=10#
#x=-2,# #y=5#
#x=-1,# #y=0#
#x=0,# #y=5#
#x=1,# #y=10#
#x=2,# #y=15#
#x=3,# #y=20#

Plot the points, then connect the dots. You should have a v-shaped graph.

graph{y=abs(5x+5) [-16.42, 15.6, -2.69, 13.33]}

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