Question

как решить с помощью дискременанта ? даю 100 баллов​

Answer 1

$\displaystyle\bf\\\frac{x^{2} +2x}{2} =\frac{x^{2}+24 }{7} \\\\\\\frac{x^{2} +2x}{2} \cdot 14=\frac{x^{2}+24 }{7} \cdot 14\\\\\\=(x^{2} +2x)\cdot 7=(x^{2} +24)\cdot 2\\\\7x^{2} +14x=2x^{2} +48\\\\7x^{2} +14x-2x^{2} -48=0\\\\5x^{2} +14x-48=0\\\\D=14^{2}-4\cdot 5\cdot(-48)= 196+960=1156=34^{2} \\\\\\x_{1} =\frac{-14-34}{10} =\frac{-48}{10} =-4,8\\\\\\x_{2} =\frac{-14+34}{10} =\frac{20}{10} =2\\\\\\Otvet \ : \ -4,8 \ ; \ 2$