Question

x²–4=3x equações de 2°grau

Answer 1

$x^{2} -4=3x\\ x^{2} -3x-4=0\\ \Delta=(3)^2-4.1.(-4) = 25\\\\ x= \frac{3+- \sqrt{25} }{2.1} = \frac{3+- 5 }{2}\\\\ x_1= \frac{3+5}{2} =4\\\\ x_2= \frac{3-5}{2} = -1$