In mathematics, more precisely in algebra, an indeterminate is a quantity that is not known, and cannot be solved for. An indeterminate is different from a variable, which is solvable, at least conditionally, from a given equation or set of equations. To make this distinction in an example, compare these two situations.

1. Let x be a variable such that

2 + 3x = a + bx,

where a and b are some rational numbers. Then, we can solve for x, to find

x = (a - 2) / (3 - b).

Any values of a and b with b not 3 will yield a value for x.

2. Let x be an indeterminate such that

2 + 3x = a + bx,

where a and b are again rational numbers. Since x cannot be solved for, we must have 2 = a and 3 = b.

See also

• Polynomial