Question

Me ajudem por favor
X² -2X-3=0 ​

Answer 1

Resposta:

$x^2-2x-3=0\\\\x_{1,\:2}=\frac{-\left(-2\right)\pm \sqrt{\left(-2\right)^2-4\cdot \:1\cdot \left(-3\right)}}{2\cdot \:1}\\\\x_{1,\:2}=\frac{-\left(-2\right)\pm \:4}{2\cdot \:1}\\\\x_1=\frac{-\left(-2\right)+4}{2\cdot \:1},\:x_2=\frac{-\left(-2\right)-4}{2\cdot \:1}\\\\x=3,\:x=-1$