Write a quadratic equation in standard form for the given pair of roots x = 2/5 and x = -3.
a) 5x² - 7x + 6 = 0
b) 5x² + 7x - 6 = 0
c) 5x² - 7x - 6 = 0
d) 5x² + 7x + 6 = 0