Question

Enter a number in the box so that the equation will have an infinite number of solutions.
4x84x + ?

Answer 1

I’m not sure how to read the equation you typed. Could you retype it showing exactly where the box goes (for example “4x □ 84x + □” or “4x = 84x + □”)?

General rule you can use: an equation has infinitely many solutions only when it is an identity — both sides are the same expression for every x. That means the coefficients of x on each side must be equal and the constant terms must be equal. So to make the equation hold for all x, choose the number(s) so the two sides match term-by-term.

Two common interpretations and their answers:
- If the equation is 4x = 84x + c, no value of c will make this true for every x (coefficients 4 and 84 differ), so there is no number that gives infinitely many solutions.
- If the equation is 4x + 8 = 4x + c, choose c = 8 (then both sides are identical and every x is a solution).

Tell me the exact equation (show the box position) and I’ll give the specific number.