Libellus de Numeros

What is the missing variable?Alex, a young precocious girl, mysteriously gets transported to a strange world where Latin and Math combine in formulas and equations with magical effects. With a cruel council leading the only safe city of it's kind in this world, she will have to prove her worth to stay as well as help this city as it is the target for two evil wizards who seek to destroy the city and it's ruling council.Will the council's mighty army of guardians be enough to repel the onsla...