Let the variable of the equation be x.
Solution of the equation is given to us, hence,
x = -3 and x = 9
x + 3 = 0 and x - 9 = 0
Multiplying,
(x + 3)(x - 9) = x² - 9x + 3x - 27 = x² - 6x - 27
Hence, the linear equation with solution -3 and 9 is x² - 6x - 27.