Question

x²-3x-40=0 formula general​

Answer 1

Respuesta:

$x=8 ; x=-5$

Explicación paso a paso:

$x^{2} -3x-40=0\\\\x=\frac{-b+-\sqrt{b^{2} -4ac} }{2a} \\x=\frac{-(-3)+-\sqrt{(-3)^{2} -4(1)(-40)} }{2}\\x=\frac{3+-\sqrt{9+160} }{2}\\x=\frac{3+-\sqrt{169} }{2}\\\\x_{1} =\frac{3+\sqrt{169} }{2}\\x_{1} =\frac{3+13 }{2}\\x_{1} =\frac{16 }{2}\\x_{1} =8\\\\x_{2} =\frac{3-\sqrt{169} }{2}\\x_{2} =\frac{3-13 }{2}\\x_{2} =\frac{-10 }{2}\\x_{2} =-5$