#### Answer

x=-$\frac{5}{9}$ or $\frac{5}{9}$

#### Work Step by Step

Rewrite the equation so it is in standard form.
81x$^2$=25
81x$^2$-25=0
Factor the binomial using the formula for factoring a difference of squares.
(9x+5)(9x-5)=0
Set each variable factor as equal to zero and then isolate the variable to find the solutions.
9x+5=0 or 9x-5=0
9x=-5 or 9x=5
x=-$\frac{5}{9}$ or x=$\frac{5}{9}$
Enter the equation into your graphing utility to observe that the graph crosses the x-axis at -$\frac{5}{9}$ and $\frac{5}{9}$.