10 pts, algebra - easy
explain which basic moves transform the equation
6x + 2y = 15 into 0 = 15 - 6x - 2y

If you would like to transform the equation 6*x + 2*y = 15 into the equation 0 = 15 - 6*x - 2*y, you have to do two following steps or you can do this at the same time (and you have to do just one step).

First, you have to subtract 6*x from both sides of the equation:
6*x + 2*y = 15   /-6*x
6*x + 2*y - 6*x = 15 - 6*x
2*y = 15 - 6*x

Second, you have to subtract 2*y from both sides of the equation:
2*y = 15 - 6*x   /-2*y
2*y - 2*y = 15 - 6*x - 2*y

The result:
0 = 15 - 6*x - 2*y

6x + 2y = 15

Subtract 6x on both sides.

2y = 15 - 6x

Next, subtract 2y on both sides.

0 = 15 - 6x - 2y

The two basic moves that we did were subtraction.