Answer:
[tex](10x - 3a)(3x + 39)(5x - 3) = 0 \\ dealing \: with \: (10x - 3a) \: and \: (5x - 3) \\ (10x - 3a)(5x - 3) = 0 \\ 50 {x}^{2} - (30 + 15a)x + 9a = 0 \\ sum \: of \: the \: equation \: = (30 + 15a) = - 1 \\ 15a = - 31 \\ a = - \frac{31}{15} [/tex]
