Given (x-2) is a factor of ax^3 + ax^2 + ax - 42, find the value of a

let f(x) = ax^3 + ax^2 + ax - 42if x-2 is a factor of f(x), then by remainder theorem, f(2) = 0and:a(2)^3 + a(2)^2 + a(2) -42 = 08a + 4a + 2a - 42 = 014a = 42a = 3