Even or odd functions ! pls! which of the graphs represent an even function? i think it's the first one.

An even function is one symmetrical about the line x=0, or the y axis. A function is odd if f(-x)=-f(x). Starting from the back, since it's only on the right side of x=0, this clearly isn't right. Next, since we have the U shape on the right and not on the left, this isn't the answer we're looking for. After that, this seems right with the same design on both sides of x=0. The leftmost graph is not correct due to that x=1 and x=-1 are different - they should be the same.

The second graph to the left is therefore right 

Just divide the x axis (the top) by 2 or multiply the y axis (the bottom) by 2