Question 38398
{{{2x^2 + 7 = 21}}} subtract seven to each side in order to get 'x' on one side
{{{2x^2 = 14}}} divide by 2 to get 'x' on one side
{{{x^2 = 7}}} square root each side in order to get 'x' equaling a number
{{{x =(7)^(1/2)}}} or {{{x =-(7)^(1/2)}}}