For the given equation, y = 4|x| - 1, what is the value of y for x = 2?

Those lines on the sides of x in the equation mean "absolute value". Which is a complicated way of saying "this number will never be negative". So if x = 2 then absolute value x = 2 but if x = - 2 then absolute value x still is positive 2. Because of those brackets/lines (whatever they're called). So if you're given x=2 then it's simply saying y=4 (2) - 1 which is y=7