Which of the following equations is of a parabola with a vertex at (1, -1)?

y = (x - 1)2 - 1
y = (x - 1)2 + 1
y = (x + 1)2 - 1
y = (x + 1)2 + 1

d. you cannot tell because there are no values shown.

if you get paid hourly because if you get a salary you could work all week and only get paid a certain amount no matter how much you work but if you get paid hourly then you get paid for every minute you worked.