@Lady fate
So, consecutive numbers are numbers that are next to each other on a number line, 1, 2, 3 for example, ir 45, 46, 47, or -1,0,1. The sum of numbers in the result of them being added together, so which of the sets for questions 1, 2, and 4 follows these rules to get the number you want?
For the rectangular prism problem, you have to move the terms around. You're working with variables so that tends to keep things neater which is fortunate. You're trying to isolate a single variable (which becomes super important for later maths). To start, locate the variable you want, in this case P. Since P is multiplied to something, we want to try and keep the term that P is part of isolated on its side of the equals sign. Remeber, what you do to one side of the equals sign you must always do to the other. In order to cancel out the 2B thats on P's side of the equation, we need to add something to both sides of the equation that will cancel that out. Its added on. How would one make a 0+1 equal to 0? The answer is the same here. Once that's done there should only be the term PH left on P's side. We have to apply another function to both sides of the equation again so that this time the H cancels out on P's side. In cases like this we divide by the term we want to get rid of. If a term exists in the same form in both the numerator and the demoninatoer, it cancels.
For the last one, try taking what is said and making it into an equation. Since there's an unknown number, put x in as its substitute. Once thats done, just solve for x

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