Question

8) x ( x + 3) – 40 = 0 responda essa pergunta

Answer 1

x ( x + 3) – 40 = 0

x² +3x -40=0

∆=9+160= 169 => √∆=13

x' = -b+√∆/2a = -3+13/2 =10/2 = 5 ✓

x"= -b-√∆/2a = -3-13/2 = -16/2 = -8 ✓

Answer 2

Explicação passo-a-passo:

$x(x + 3) - 40 = 0 \\ {x}^{2} + 3x - 40 = 0$

/\=b^2-4.ac

/\=(3)^2-4.1.(-40)

/\=9+160

/\=169

$x = \frac{ - b \frac{ + }{ - }raiz \: de \: delta }{2.a} \\ {x}^{1} = \frac{ - 3 + 13}{2} \\ {x}^{1} = \frac{10}{2} \\ {x}^{1} = 5 \\ \\ {x}^{2} = \frac{ - 3 - 13}{2} \\ {x}^{2} = \frac{ - 16}{2} \\ {x}^{2} = - 8$logo x1=5 e x2=-8