X2+(4a-3)x-12a=0
Дискриминат, х 1,2

х²+(4a-3)x-12a=0

a = 1
b = 4a-3
c = - 12
D = b² - 4ac
D = (4a-3)² - 4·1·(-12) = 16a²-24a+9+48 = 16a²-24a+57
√D = √(16a²-24a+57)

x₁ = (-4a+3+√(16a²-24a+57))/2;
x₂ = (-4a+3-√(16a²-24a+57))/2;