Question

Решите уравнение -x-5= и все под корням 7x+23

Answer 1

-х-5=√7х+23
(-х-5)^2=7х+23
х^2+10х+25=7х+23
х^2+3х+2=0
х=-1 х=-2

Answer 2

$- x - 5 = sqrt{7x + 23 } \ {( - x - 5)}^{2} = { sqrt{7x + 23} }^{2} \ {x}^{2} + 10x + 25 = 7x + 23 \ {x}^{2} + 10x + 25 - 7x - 23 = 0 \ {x}^{2} + 3x + 2 = 0 \ d = {3}^{2} - 4 times 1 times 2 = 9 - 8 = 1 \ sqrt{d} = 1 \ x1 = frac{ - 3 + 1}{2} = frac{ - 2}{2} = - 1 \ x2 = frac{ - 3 - 1}{2} = frac{ - 4}{2} = - 2$
Ответ: x1=-1; x2=-2.