Question

Inequação do 2 grau
X²-7x ≤ 2x-14

Answer 1

$x^{2} - 7x \leqslant 2x - 14 \\ {x}^{2} - 7x - 2x \leqslant - 14 \\ {x}^{2} - 9x \leqslant - 14 \\ {x}^{2} - 9x + 14 \leqslant 0 \\ resolvendo \: com \: baskara$
$delta = b^{2} - 4.a.c$
[tex]delta = -9^{2} - 4.1.14 \\ delta = 81 - 56 \\ delta = 25[tex]

Answer 2

$x^{2} -7x \leq 2x-14 \\ \\ x^{2} -7x-2x+14 \leq 0 \\ \\ x^{2} -9x+14=0 \\ \\ a=1 \\ b=-9 \\ c=14 \\ \\ \Delta=b^2-4ac \\ \Delta=(-9)^2-4(1)(14) \\ \Delta=81-56 \\ \Delta=25 \\ \\ x= \frac{-b\pm \sqrt{\Delta} }{2a} = \frac{-(-9)\pm \sqrt{25} }{2} = \frac{9\pm5}{2} \\ \\ x'= \frac{9-5}{2} = \frac{4}{2} =2 \\ \\ x"= \frac{9+5}{2} = \frac{14}{2} =7$~

$++++\bullet^2----\bullet^7++++ \\ ~~~m/a~~~~~~~~~~c/a~~~~~~~~~~~~m/a \\ \\ \\ como~~pediu~~ \leq ~0 \\ \\ S=\{x\in R/2 \leq x \leq 7\}$