An expression is just some combination of numbers and symbols....example.........
3 + 5
2x - 9
5x^7 - 2x^2 + 3
sqrt(3) + 28 .
etc.
An equation implies an "equal" sign with an expression on each side of the sign....example....
2x = 8x - 3
5x - 9 = 4x - 2
sqrt(3x) = 25
etc.
