Question

resolva :

${x}^{2} - 2x + 15 = 0$

Answer 1

X^2-2x+15
▲= (-2)^2-4×1×15
▲= 4+60
▲=64

X= -(-2)+- raiz de 64
X= 2+-8
X1= 2+8/2=10/2=5
X2= 2-8/2= -6/2= -3 S={-3; 5}