One equivalent equation could just be the numbers 2.5 and 5 distributed.
2.5(12-2x)+5(x+1)
= 30 - 5x + 5x + 5
Another equivalent equation could be the distribution of those numbers again and also the combination of like terms.
2.5(12-2x)+5(x+1)
30 - 5x + 5x + 5
= 35