Question

-x ao quadrado -12=-7x

Answer 1

$- x^{2} -12=-7x\to\\\\ - x^{2}+7x -12=0\\\\ a=-1;b=7;c=-12\\\\ \Delta=b^2-4ac\to \Delta=7^2-4*(-1)*(-12)\to \Delta=49-48\to \Delta=1\\\\\\ x'=x''\\\\\\ x= \frac{-b\pm \sqrt{\Delta} }{2a} \to x= \frac{-7\pm \sqrt{1} }{2*(-1)} \to x= \frac{-7\pm 1 }{-2} \to \\\\\\ x'= \frac{-7+ 1 }{-2} \to x= \frac{-6 }{-2} \to x'=3\\\\\\ x''= \frac{-7- 1 }{-2} \to x''= \frac{-8 }{-2} \to x''=4\\\\\\\\ S=(3;4)$