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# How do we represent a Gate involving a constant to the left or right of the operator in PLONK?

Let's say I have the following equation to be arithmetised in PLONK

$$x^3 + x + 5 = 35$$ and the witness is $$x = 3$$

$$3 * 3 = 9$$

$$9 * 3 = 27$$

$$27 + 3 = 30$$

$$30 + 5 = 35$$

Now the 4th gate can be expressed as

1. $$Q_l\cdot 30 + Q_r\cdot 5 + Q_m(30\cdot 5) + Q_c + Q_o\cdot(35)$$

with $$Q_l = 1, Q_r = 1, Q_m = 0, Q_c = 0, Q_o = -1$$

Or as

1. $$Q_l\cdot 30 + Q_r\cdot ? + Q_m(30\cdot ?) + Q_c + Q_o\cdot(35)$$

with $$Q_l = 1, Q_r = 1$$ or $$0, Q_m = 0, Q_c = 5, Q_o = -1$$

In the first case, the element of the $$b$$ vector would be 5.

But in the second case, the element of the $$b$$ vector can be anything - it doesn't matter if $$Q_r = 0$$ but $$b$$ vector element needs to be $$0$$ if $$Q_r = 1$$.

So which of these 2 methods is the right way to represent the 4th gate. If it's the 2nd way, then should $$Q_r$$ be $$0$$ or $$1$$ & what should be the $$b$$ vector element?

I sit in a Tesla and translated this thread with Ai: