We can find the value of an expression when given the values of \(x\), \(y\), etc. To find the value of an expression, we need to substitute the given values for \(x\) and \(y\) into \(3x + 5y\).

Parsing algebraic expressions is always a pain. If you need to compute, say, 2+4*2, the answer should be the same as (2 + (4 *2)), not ((2 + 4) * 2) — in other words, the right answer is 10 ...

Formulae contain equals signs, as do equations, so it can sometimes be difficult to tell the difference between an equation and a formula.

Therefore, he figured, no general formula could solve them. Approximate solutions for higher-degree polynomials ... Aside from theoretical interest, he says, the method holds practical promise for ...

Therefore, he figured, no general formula could solve them ... promise for creating computer programs that can solve equations using the algebraic series rather than radicals.