Answer:
[tex] \huge \: \boxed{ \boxed{21}}[/tex]
Step-by-step explanation:
according to the question
[tex] \frac{14}{2x + 7} = \frac{x - 3}{63} [/tex]
[tex]882 = (x - 3)(2x + 7)[/tex]
[tex]0 =882 - (x - 3)(2x + 7)[/tex]
[tex] 882 - (2 {x}^{2} + x - 21) = 0[/tex]
[tex]882 - {2x}^{2} - x + 21 = 0[/tex]
[tex] - {2x}^{2} - x + 903 = 0[/tex]
[tex]2x + x - 903 = 0[/tex]
[tex](2x + 43)(x - 21) = 0[/tex]
[tex]x = - \frac{43}{2} \\ x = 21[/tex]
[tex] \huge \therefore x = 21[/tex]
