Question

x2 -5x +4 =0 (x ao quadrado )​

Answer 1

${x}^{2} - 5x + 4 = 0 \\ a = 1 \\ b = - 5\\ c = 4 \\ \\ d = {b}^{2} - 4ac\\ d = {( - 5)}^{2} - 4 \times 1 \times 4 \\ d = 25 - 16 \\ d = 9 \\ \sqrt{d} = 3 \\ \\ x1 = \frac{ - b + \sqrt{d} }{2 \times a} \\ x1 = \frac{ - ( - 5) + 3}{2 \times 1} = \frac{5 + 3}{2} = \frac{8}{2} = 4 \\ \\ x2 = \frac{ - b - \sqrt{d} }{2 \times a} \\ x2 = \frac{ 5 - 3}{2} = \frac{2}{2} = 1$

Espero ter ajudado!! ^_^