5x plus 3 does equal 3 plus 5x; commutative law.
4x3+6x7 = (4x3)+(6x7) = 12+42 = 54 in the rules of calculation the times has to be done before the plus so the 6x7 must be figured out before you can add.
-10x + 5x = -5x
It is: 4X+X = 5X
It is: 5x
10x - 5x + 5x = 10x
5x+5x-10 10x-10 is the only answer you can get from this
5x+2x=7x2x + 5x = 7x
-5x^2 - 55x - 120