a. B is two different prime numbers. If a + B = 20, a * b = 51, then what are a and B respectively a. B is two different prime numbers. If a + B = 20, a * b = 51, then what are a and B respectively, the formula, method and idea should all be adopted,

a. B is two different prime numbers. If a + B = 20, a * b = 51, then what are a and B respectively a. B is two different prime numbers. If a + B = 20, a * b = 51, then what are a and B respectively, the formula, method and idea should all be adopted,

A = 20-b, ab = 51