Question

determine o valor da equacao 3-2x[x+3]=x-18

Answer 1

3 - 2x² - 6x = x - 18
3 - 2x² - 6x - x +18 = 0
-2x² - 7x + 21 = 0
Δ = b² - 4ac
Δ = 49 + 168
Δ = 117
x = 7 +- √117/-4
x´= 7 + 10,8/-4
x´= 17,8/-4 = - 4,45
x´´ = 7 - 10,8/-4
x'' = -3,8/-4 = 0,95              ok