# Rubik’s Cube – Solving a Cross

#### Description

Rubik’s Cube expert Bob Burton demonstrates how to solve a cross on your Rubik’s cube puzzle.

#### Expert

Bob Burton

Bob is a math teacher at a high school in New York City. He received his B.A. in mathematics from Rutgers University and is currently pursuing a M.A. in mathematics education from the City College of New York. He also has a great interest in the sciences, especially physics and chemistry. Bob has been solving Rubik's Cubes since 2001 and competed in over twenty official contests all over the world. He has held several world records and national titles for Rubik's puzzles, including the Rubik's Magic and Square-1. At Rutgers University, Bob founded the RU Rubik's Cube Club, which hosted official competitions twice each year, attracting competitors from all over the country in addition to several international competitors. He has also developed several fingertricks for Rubik's Cube algorithms that are used by some of the fastest speedcubers in the world. Bob is also the webmaster for cubewhiz.com, a site designed for speedcubers to learn new tricks and become faster. He currently averages about twenty seconds to solve a Rubik's Cube with a personal best of 13 seconds. He has even solved the puzzle blindfolded in several official competitions. Bob currently lives with his family in Kearny, New Jersey.

#### Transcript

Hi, I am Bob Burton, Rubik's Cube Expert, and I am teaching you how to solve Rubik's cube. The first step to solving the puzzle is to solve the cross on the first face of the Rubik's cube. The first face that I will show you is white just because it sits out the best.

The first thing you want to do is look for any cross pieces that are already lined up with the color that they belong with. Remember, that the centers of the Rubik's cube puzzle are fixed. So, if you see, for example, this edge piece, which has two stickers, its already connected to centerpiece that it belongs with, you can move it freely to match up with the centerpiece of white. So, this is actually the first piece solved.

We will then look for more pieces that we can do this with. If you look at this red piece, it was only one move to line up the red edge with the red center. Once we have it like that, its only again, one move to match the white.

We then look for another piece. This one is blue. Again, you will see that blue only takes one move, and then we can put it back to match the white. There is one more piece that we need to solve is the orange one. The orange one is also one move to line up. Once we have it lined up with the orange center, we can move it all the way up to the top of the Rubik's cube. This is a completed white cross.

Sometimes you will get more difficult case to show up. Sometimes you can't actually have the orange match up with the orange center, or another piece not match up with its own center. In this case what you do is you bring the edge down to a middle layer. You look for the piece that it belongs with. For example, orange belongs between blue and green. We look for the blue and green edges, move them over, so that orange lines up right in between them. We put it in place, and then we restore the first move we made, that took the blue and green edges away from where they belong. That's it for solving the first step of the Rubik's cube puzzle. Next I will show you how to solve the first layer points of the Rubik's cube.

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