Question

x ^ 2 - 2 a x - 3 a ^ 2=0

Answer 1

D=(-2a)²-4*1*(-3a²)=4a²+12a²=16a², D>0
x1,2=(±√(16a²)-(-2a))/(2*1)=(±4a+2a)/2
x1=3a, x2=-a