Question

AJUDA URGENTE NAS QUESTÕES DA IMAGEM

Answer 1

     03)
                    $x^3-34x^2+225=0$

                    Introduzindo mudança de variável $y=x^{2}$
                    a equação fica
                                                  $y^2-34y+225=0$

                    Resolvendo por fatoração
                                                  (y - 25)(y - 9) = 0
                                                           y - 25 = 0
                                                                              y1 = 25
                                                           y - 9 = 0
                                                                              y2 = 9
                   
                    Voltando à variável original, para cada valor obtido
                                                           $x^2 = y \\ \\ x^2=25 \\ x1=-5 \\ x2=5 \\ \\ x^2=9 \\ x3=-3 \\ x4=3$

                                                                         S = { - 5, - 3, 3, 5 }
                                                          

    01)
                        base = b               b > h
                        altura = h = b - 3
                        A = (b x h)/2
                        27 = [b x (b - 3)]/2
                        54 = b^2 - 3b
                        b^2 - 3b - 54 = 0
                 fatorando
                        (b - 9)(b + 6) = 0
                                         b - 9 = 0
                                                          b1 = 9
                                         b + 6 = 0
                                                          b2 = - 6 DESCARTA POR SE NEGATIVO
               Então
                          base = 9
                          altura = 6  (9 - 3)