algebra
posted by Tatyanna .
34x(nx2)=680

Online, "*" is used to indicate multiplication, because "x" is often used to stand for an unknown. Exponents are indicated by "^".
I'm not sure if you mean:
34x(nx^2) = 680 or
34 * 2n = 680
68n = 680
n = 10
The first version cannot be solved, because there are two unknowns (x and n).