Question 392208
{{{27r^2-72 = 0}}} Factor 9.
{{{9(3r^2-8) = 0}}} so...
{{{3r^2-8 = 0}}} Add 8 to both sides.
{{{3r^2 = 8}}} Divide both sides by 3.
{{{r^2 = 8/3}}} Take the square root.
{{{r = sqrt(8/3)}}}