Question Use the square roots property to solve the quadratic equation \( 4 a^{2}=36 \). If there are multiple answers, list them separated by a comma, e.g. 1, 2. If there is no real solution, enter \( \varnothing \)

To solve the equation \( 4a^2 = 36 \), first, divide both sides by 4 to simplify it: \( a^2 = 9 \). Next, apply the square roots property, which tells us that if \( a^2 = b \), then \( a = \pm\sqrt{b} \). Here, \( b = 9 \). Thus, \( a = \pm\sqrt{9} = \pm3 \). The solutions are \( 3, -3 \).