I posted this question yesterday and I got a response that is correct but I still don't understand how he got it. What did he do with the 2?

how do i find the slope of the curve at the indicated point?

f(x)= absolute value of x, x=2

math - bobpursley, Wednesday, September 16, 2009 at 7:50pm
at x=2, abs(x)= x

f(x)=x
slope= 1

1 answer

f(x) = │x│
or
y = │x│

resulting in two linear functions
y = x , y = -x , where y ≥ 0

the graph will be a V-shape with the vertex at the origin.

here are a couple of ordered pairs,
for x>0, (1,1),(3,3),.. (12,12) etc
for x< 0
(-1,1),(-3,3) etc

so for x>0 the slope is +1
for x<0 the slope is -1