[tex] \frac{4 {x}^{2} + 5x }{14} + \frac{10 - 2 {x}^{2} }{7} = 5 \\ \frac{4 {x}^{2} + 5x }{14} + \frac{2(10 - 2 {x}^{2} )}{14} = 5 \\ \frac{4 {x}^{2} + 5x + 20 - 4{x}^{2} }{14} = 5 \\ \frac{5x + 20}{14} = 5 \\5x + 20 = 70 \\ 5x = 50 \\x = 10[/tex]