[tex]\frac{a}{b} =\frac{2}{5} \\a*b = 150\\[/tex]
Din prima ecuatie avem:
[tex]5a = 2b => a = \frac{2b}{5}\\[/tex]
Deci:
[tex]\frac{2b}{5} * b = 150\\ 2b^{2} = 750\\b^2 = 375\\b = \sqrt{375} \\\\a = \frac{2* \sqrt{375} }{5}\\ \\a+ b = \frac{2* \sqrt{375} }{5} + \sqrt{375} = S\\2\sqrt{375} + 5\sqrt{375}=5S\\ S = a+b = \frac{7\sqrt{375} }{5}[/tex]
