Question 884878
Start with the absolute value function y = |x|


Stretch it by a factor of 2 to get y = 2*|x|


Then shift everything down 1 unit to get y = 2*|x| - 1


So the graph looks like


{{{ drawing( 500, 500, -10, 10, -10, 10,
grid(1),
graph( 500, 500, -10, 10, -10, 10, 0, 2*abs(x)-1)

) 
}}}