Answer
$$q = \pm2$$
Work Step by Step
First you add 20 to both sides
$$5q^2 = 20$$
Then you divide both sides by 5
$$q^2 = 4$$
Then you find the square root of both sides
$$q = \pm2$$
That is your final answer since the variable is alone now. Remember you always have to put the plus or minus sign ($\pm$) because any number under the square root that is above $0$ has $2$ has answers.
